NBM GRIB All Sections

 

IS0: Indicator Section

Standard

octet(s) octet content value description
1-4 "grib" definition 1196575042  
5-6 reserved    
7 discipline 0 meteorological
8 grib edition number 2  
9 total length of grib message in octets varies  

maxffwi/maxhi

octet(s) octet content value description
1-4 "grib" definition 1196575042  
5-6 reserved    
7 discipline 2 land surface
8 grib edition number 2  
9 total length of grib message in octets varies  

sigwv

octet(s) octet content value description
1-4 "grib" definition 1196575042  
5-6 reserved    
7 discipline 10 oceanographic
8 grib edition number 2  
9 total length of grib message in octets varies  

 

IS1: Identification Section

 

Standard

octet(s) octet content value description
1-4 length of section in octets 21  
5 section number 1  
6-7 ID of originating center 7 National Weather Service - NCEP
8-9 ID of origin sub-center 14 MDL
10 GRIB master tables version number ** 1  
11 GRIB local tables' version number 0 Local tables not used
12 significance of reference time 1 start of forecast
13-14 Year varies  
15 Month varies  
16 Day varies  
17 Hour 0  
18 Minute 0  
19 Second 0  
20 Production Status of Processed data in the GRIB message 0 operational product
21 Type of processed data in this GRIB message 1 forecast products

Note

**Previously NBM v3.1 used Master Table number 19. Due to a bug, old versions of degrib may not be able to read the new nbm grib files that use Grib Master Table 19. Please update to the newest version of degrib to read the older files. To download, go to our Degrib Page

dryts03

octet(s) octet content value description
1-4 length of section in octets 21  
5 section number 1  
6-7 ID of originating center 7 National Weather Service - NCEP
8-9 ID of origin sub-center 9 US National Weather Service - Other (WMC)
10 GRIB master tables version number 2 Version Implemented on 4 November 2003
11 GRIB local tables' version number 1 local table version 1 used
12 significance of reference time 1 start of forecast
13-14 Year varies  
15 Month varies  
16 Day varies  
17 Hour 0  
18 Minute 0  
19 Second 0  
20 Production Status of Processed data in the GRIB message 1 operational test product
21 Type of processed data in this GRIB message 1 forecast products

 

IS2: Local Use Section

Standard (all except predomwx)

 

Do not use Section 2. All values are 0. 

 

predomwx

octet(s) octet content value description
1-4 Length of the section in octets varies  
5 Number of the section 2  
6 Local Use Format 1 MDL Local Use Template 2.1

 

IS3: Grid Definition Section

IS3 Groups

Section 3 defines the grid, and therefore grib2 information is presented by data region. (Although certain elements may have different regional settings):

 

CONUS (standard)

octet(s) content value meaning notes
1-4 Length of the section 81    
5 section number 3    
6 Source of grid definition 0   Specified in Code - oct 3.13
7-10 Number of data points 3744965    
11 Number of octets for optional list of numbers defining number of points 0 grid is regular; no appended data  
12 Interpretation of list of numbers defining number of points 0 There is no appended list  
13-14 Grid definition template number 30 Lambert Conformal Can be Secant, Tangent, Conical, or Bipolar;
15 Shape of the Earth 1 Earth assumed spherical with radius specified (in m) by data producer  
16 Scale factor of radius of spherical Earth 0    
17-20 Scale value of radius of spherical Earth 6371200    
21 Scale factor of major axis of oblate spheroid Earth 255    
22-25 Scaled value of major axis of oblate spheroid Earth 255    
26 Scale factor of minor axis of oblate spheroid Earth 255    
27-30 Scaled value of minor axis of oblate spheroid Earth 255    
31-34 Nx ― number of points along the x-axis 2345    
35-38 Ny — number of points along the y-axis 1597    
39-42 La1― latitude of first grid point 19229000    
43-46 Lo1― longitude of first grid point 233723400    
47 Resolution and component flags 48 i direction increments given; j direction increments given; Resolved u and v components of vector quantities relative to easterly and northerly directions convert value to binary to read in table 3.3 (48 = 00110000)
48-51 LaD ― latitude where Dx and Dy are specified 25000000    
52-55 LoV ― longitude of meridian parallel to y-axis along which latitude increases as the y-coordinate increases 265000000    
56-59 Dx ― x-direction grid length 2539703   Grid length is in units of 10-3 m at the latitude specified by LaD
60-63 Dy ― y-direction grid length 2539703   Grid length is in units of 10-3 m at the latitude specified by LaD
64 Projection centre flag 0 North Pole is on the projection plane; Only one projection center is used convert value to binary to read in table 3.5 (0 = 00000000)
65 Scanning mode 64 Points in the first row or column scan in the +i (+x) direction; Points in the first row or column scan in the +j (+y) direction; Adjacent points in the i (x) direction are consecutive; All rows scan in the same direction; Points within odd rows are not offset in i(x) direction; Points within even rows are not offset in i(x) direction; Points are not offset in j(y) direction; Rows have Ni grid points and columns have Nj grid points convert value to binary to read in table 3.4 (64 = 01000000)
66 Latin 1 ― first latitude from the pole at which the secant cone cuts the sphere 25000000    
70 Latin 2 ― second latitude from the pole at which the secant cone cuts the sphere 25000000    
74-77 Latitude of the southern pole of projection -90   For tstm03 this =0; for all others output read=4204967296 (for non-tstorm) Doesn't seem to be a valid entry; output degrib text=0-90; perhaps it is a bug in code for read-out for -90 value (after corrections)?;
78-81 Longitude of the southern pole of projection 0    

 

CONUS (dryts03)

octet(s) content value meaning notes
1-4 Length of the section 81    
5 section number 3    
6 Source of grid definition 0    
7-10 Number of data points 3744965    
11 Number of octets for optional list of numbers defining number of points 0 grid is regular; no appended data  
12 Interpetation of list of numbers defining number of points 0 There is no appended list  
13-14 Grid definition template number 30 Lambert Conformal  
15 Shape of the Earth 6 Earth assumed spherical with radius = 6,371,229.0  
16 Scale factor of radius of spherical Earth 0    
17-20 Scale value of radius of spherical Earth 0    
21 Scale factor of major axis of oblate spheroid Earth 0    
22-25 Scaled value of major axis of oblate spheroid Earth 0    
26 Scale factor of minor axis of oblate spheroid Earth 0    
27-30 Scaled value of minor axis of oblate spheroid Earth 0    
31-34 Nx ― number of points along the x-axis 2345    
35-38 Ny — number of points along the y-axis 1597    
39-42 La1― latitude of first grid point 19229000    
43-46 Lo1― longitude of first grid point 233723400    
47 Resolution and component flags 56 i direction increments given; j direction increments given; Resolved u and v components of vector quantities relative to the defined grid in the direction of increasing x and y (or i and j) coordinates, respectively convert value to binary to read meaning in table 3.3 (56 =00111000)
48-51 LaD ― latitude where Dx and Dy are specified 25000000    
52-55 LoV ― longitude of meridian parallel to y-axis along which latitude increases as the y-coordinate increases 265000000    
56-59 Dx ― x-direction grid length 2539703    
60-63 Dy ― y-direction grid length 2539703    
64 Projection centre flag 0 North Pole is on the projection plane; Only one projection center is used  
65 Scanning mode 64 Points in the first row or column scan in the +i (+x) direction; Points in the first row or column scan in the +j (+y) direction; Adjacent points in the i (x) direction are consecutive; All rows scan in the same direction; Points within odd rows are not offset in i(x) direction; Points within even rows are not offset in i(x) direction; Points are not offset in j(y) direction; Rows have Ni grid points and columns have Nj grid points convert value to binary to read in table 3.4 (64 = 01000000)
66 Latin 1 ― first latitude from the pole at which the secant cone cuts the sphere 25000000    
70 Latin 2 ― second latitude from the pole at which the secant cone cuts the sphere 25000000    
74-77 Latitude of the southern pole of projection 0    
78-81 Longitude of the southern pole of projection 0    

 

Alaska

octet(s) content value meaning notes
1-4 Length of the section 65    
5 section number 3    
6 Source of grid definition 0 Specified in Code - oct 3.13  
7-10 Number of data points 1822145    
11 Number of octets for optional list of numbers defining number of points 0 grid is regular; no appended data  
12 Interpretation of list of numbers defining number of points 0 There is no appended list  
13-14 Grid definition template number 20 Polar Stereographic  
15 Shape of the Earth 1 Earth assumed spherical with radius specified (in m) by data producer  
16 Scale factor of radius of spherical Earth 0    
17-20 Scale value of radius of spherical Earth 6371200    
21 Scale factor of major axis of oblate spheroid Earth 255    
22-25 Scaled value of major axis of oblate spheroid Earth 255    
26 Scale factor of minor axis of oblate spheroid Earth 255    
27-30 Scaled value of minor axis of oblate spheroid Earth 255    
31-24 Nx ― number of points along the x-axis 1649    
35-38 Ny ― number of points along the y-axis 1105    
39-42 La1 ― latitude of first grid point 40530000    
43-46 Lo1 ― longitude of first grid point 181429000    
47 Resolution and component flags 48 i direction increments given; j direction increments given; Resolved u and v components of vector quantities relative to easterly and northerly directions convert value to binary to read in table 3.3 (48 = 00110000)
48-51 LaD ― latitude where Dx and Dy are specified 60000000    
52-55 LoV ― orientation of the grid 210000000   "LoV is the longitude value of the meridian which is parallel to the y-axis (or columns of the grid) along which latitude increases as the y-coordinate increases (the orientation longitude may or may not appear on a particular grid)."
56-59 Dx ― x-direction grid length 2976560   Grid length is in units of 10-3 m at the latitude specified by LaD
60-63 Dy ― y-direction grid length 2976560   Grid length is in units of 10-3 m at the latitude specified by LaD
64 Projection centre flag 0 North Pole is on the projection plane; Only one projection center is used convert value to binary to read in table 3.5 (0 = 00000000)
65 Scanning mode 64 Points in the first row or column scan in the +i (+x) direction; Points in the first row or column scan in the +j (+y) direction; Adjacent points in the i (x) direction are consecutive; All rows scan in the same direction; Points within odd rows are not offset in i(x) direction; Points within even rows are not offset in i(x) direction; Points are not offset in j(y) direction; Rows have Ni grid points and columns have Nj grid points convert value to binary to read in table 3.4 (64 = 01000000)

 

Hawaii

octet(s) content value meaning notes
1-4 Length of the section 72    
5 section number 3    
6 Source of grid definition 0 Specified in Code - oct 3.13  
7-10 Number of data points 350625    
11 Number of octets for optional list of numbers defining number of points 0 grid is regular; no appended data  
12 Interpretation of list of numbers defining number of points 0 There is no appended list  
13-14 Grid definition template number 10 Mercator  
15 Shape of the Earth 1 Earth assumed spherical with radius specified (in m) by data producer  
16 Scale factor of radius of spherical Earth 0    
17-20 Scale value of radius of spherical Earth 6371200    
21 Scale factor of major axis of oblate spheroid Earth 255    
22-25 Scaled value of major axis of oblate spheroid Earth 255    
26 Scale factor of minor axis of oblate spheroid Earth 255    
27-30 Scaled value of minor axis of oblate spheroid Earth 255    
31-34 Nj—number of points along a parallel 625    
35-38 Nj—number of points along a meridian 561    
39-42 La1 ― latitude of first grid point 14351500    
43-46 Lo1 ― longitude of first grid point 195030500    
47 Resolution and component flags 0 i direction increments not given, j direction increments not given, Resolved u and v components of vector quantities relative to easterly and northerly directions convert value to binary to read meaning in table 3.3
48-51 LaD — latitude(s) at which the Mercator projection intersects the Earth (Latitude(s) where Di and Dj are specified) 20000000    
52-55 La2 ― latitude of last grid point 26860500    
56-59 Lo2 — longitude of last grid point 209959800    
60 Scanning mode 64 Points in the first row or column scan in the +i (+x) direction; Points in the first row or column scan in the +j (+y) direction; Adjacent points in the i (x) direction are consecutive; All rows scan in the same direction; Points within odd rows are not offset in i(x) direction; Points within even rows are not offset in i(x) direction; Points are not offset in j(y) direction; Rows have Ni grid points and columns have Nj grid points convert value to binary to read in table 3.4 (64 = 01000000)
61-64 Orientation of the grid, angle between i direction on the map and the Equator 200000000   Limited to the range of 0 to 90 degrees; if the angle of orientation of the grid is neither 0 nor 90 degrees, Di and Dj must be equal to each other
65-68 Dj — longitudinal direction grid length 2500000   Grid lengths are in units of 10-3 m, at the latitude specified by LaD
69-72 Dj ― latitudinal direction grid length 2500000   Grid lengths are in units of 10-3 m, at the latitude specified by LaD

 

Puerto Rico

octet(s) content value meaning notes
1-4 Length of the section 72    
5 section number 3    
6 Source of grid definition 0 Specified in Code - oct 3.13  
7-10 Number of data points 76275    
11 Number of octets for optional list of numbers defining number of points 0 grid is regular; no appended data  
12 Interpretation of list of numbers defining number of points 0 There is no appended list  
13-14 Grid definition template number 10 Mercator  
15 Shape of the Earth 1 Earth assumed spherical with radius specified (in m) by data producer  
16 Scale factor of radius of spherical Earth 0    
17-20 Scale value of radius of spherical Earth 6371200    
21 Scale factor of major axis of oblate spheroid Earth 255    
22-25 Scaled value of major axis of oblate spheroid Earth 255    
26 Scale factor of minor axis of oblate spheroid Earth 255    
27-30 Scaled value of minor axis of oblate spheroid Earth 255    
31-34 Nj—number of points along a parallel 339    
35-38 Nj—number of points along a meridian 225    
39-42 La1 ― latitude of first grid point 16977500    
43-46 Lo1 ― longitude of first grid point 291972200    
47 Resolution and component flags 0 i direction increments not given, j direction increments not given, Resolved u and v components of vector quantities relative to easterly and northerly directions convert value to binary to read meaning in table 3.3
48-51 LaD — latitude(s) at which the Mercator projection intersects the Earth (Latitude(s) where Di and Dj are specified) 20000000    
52-55 La2 ― latitude of last grid point 19522100    
56-59 Lo2 — longitude of last grid point 296015600    
60 Scanning mode 64 Points in the first row or column scan in the +i (+x) direction; Points in the first row or column scan in the +j (+y) direction; Adjacent points in the i (x) direction are consecutive; All rows scan in the same direction; Points within odd rows are not offset in i(x) direction; Points within even rows are not offset in i(x) direction; Points are not offset in j(y) direction; Rows have Ni grid points and columns have Nj grid points convert value to binary to read in table 3.4 (64 = 01000000)
61-64 Orientation of the grid, angle between i direction on the map and the Equator 295000000   Limited to the range of 0 to 90 degrees; if the angle of orientation of the grid is neither 0 nor 90 degrees, Di and Dj must be equal to each other
65-68 Dj — longitudinal direction grid length 1250000   Grid lengths are in units of 10-3 m, at the latitude specified by LaD
69-72 Dj ― latitudinal direction grid length 1250000   Grid lengths are in units of 10-3 m, at the latitude specified by LaD

 

Oceanic

octet(s) content value meaning notes
1-4 Length of the section 72    
5 section number 3    
6 Source of grid definition 0 Specified in Code - oct 3.13  
7-10 Number of data points 4573389    
11 Number of octets for optional list of numbers defining number of points 0 grid is regular; no appended data  
12 Interpretation of list of numbers defining number of points 0 There is no appended list  
13-14 Grid definition template number 10 Mercator  
15 Shape of the Earth 1 Earth assumed spherical with radius specified (in m) by data producer  
16 Scale factor of radius of spherical Earth 0    
17-20 Scale value of radius of spherical Earth 6371200    
21 Scale factor of major axis of oblate spheroid Earth 255    
22-25 Scaled value of major axis of oblate spheroid Earth 255    
26 Scale factor of minor axis of oblate spheroid Earth 255    
27-30 Scaled value of minor axis of oblate spheroid Earth 255    
31-34 Nj—number of points along a parallel 2517    
35-38 Nj—number of points along a meridian 1817    
39-42 La1 ― latitude of first grid point 4264548096    
43-46 Lo1 ― longitude of first grid point 129905800    
47 Resolution and component flags 48 i direction increments given, j direction increments given, Resolved u and v components of vector quantities relative to easterly and northerly directions convert value to binary to read meaning in table 3.3
48-51 LaD — latitude(s) at which the Mercator projection intersects the Earth (Latitude(s) where Di and Dj are specified) 20000000    
52-55 La2 ― latitude of last grid point 80383000    
56-59 Lo2 — longitude of last grid point 10689200    
60 Scanning mode 64 Points in the first row or column scan in the +i (+x) direction; Points in the first row or column scan in the +j (+y) direction; Adjacent points in the i (x) direction are consecutive; All rows scan in the same direction; Points within odd rows are not offset in i(x) direction; Points within even rows are not offset in i(x) direction; Points are not offset in j(y) direction; Rows have Ni grid points and columns have Nj grid points convert value to binary to read in table 3.4 (64 = 01000000)
61-64 Orientation of the grid, angle between i direction on the map and the Equator 0   Limited to the range of 0 to 90 degrees; if the angle of orientation of the grid is neither 0 nor 90 degrees, Di and Dj must be equal to each other
65-68 Dj — longitudinal direction grid length 10000000   Grid lengths are in units of 10-3 m, at the latitude specified by LaD
69-72 Dj ― latitudinal direction grid length 10000000   Grid lengths are in units of 10-3 m, at the latitude specified by LaD

 

IS4: Product Definition Section

Section 4 defines the product, and is therefore broken down by element. Some grib2 octets will vary by run; these can be read with a program such as degrib. Elements with similar grib2 properties have been grouped. These groups have been clustered into categories (to make them easier to find): 


CORE ELEMENTS

temp / dewp / appt

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 0 Temperature  
11 Parameter number
  1. 0
  2. 6
  3. 21
  1. Temperature
  2. Dew Point Temperature
  3. Apparent Temperature
 
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 2    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

rh

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 1 Moisture  
11 Parameter number 1 Relative Humidity  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 2    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

maxt / mint

octet(s) content value meaning notes
1-4 length of section in octets 58    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 8    
10 parameter category 0 temperature  
11 Parameter number
  1. 4
  2. 5
  1. maximum temperature (K)
  2. minimum temperature (K)
 
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 2    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35-36 Year ― Time of end of overall time interval varies    
37 Month - Time of end of overall time interval varies    
38 Day - Time of end of overall time interval varies    
39 Hour - Time of end of overall time interval varies    
40 Minute - Time of end of overall time interval varies    
41 Second - Time of end of overall time interval varies    
42 n ― number of time ranges specifications describing the time intervals used to calculate the statistically-processed field 1    
43-46 Total number of data values missing in statistical process 0    
47 Statistical process used to calculate the processed field from the field at each time increment during the time range
  1. 2
  2. 3
  1. maximum
  2. minimum
 
48 Type of time increment between successive fields used in the statistical processing 2 Successive times processed have same start time of forecast, forecast time is incremented.  
49 Indicator of unit of time for time range over which statistical processing is done 1 hour  
50-53 Length of the time range over which statistical processing is done, in units defined by the previous octet 12    
54 Indicator of unit of time for the increment between the successive fields used 1 hour  
55-58 Time increment between successive fields, in units defined by the previous octet 0    

 

maxrh / minrh

octet(s) content value meaning notes
1-4 length of section in octets 58    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 8    
10 parameter category 1 moisture  
11 Parameter number
  1. 27
  2. 198
  1. Maximum Relative Humidity (%)
  2. Minimum Relative Humidity (%)
 
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 2    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35-36 Year ― Time of end of overall time interval varies    
37 Month - Time of end of overall time interval varies    
38 Day - Time of end of overall time interval varies    
39 Hour - Time of end of overall time interval varies    
40 Minute - Time of end of overall time interval varies    
41 Second - Time of end of overall time interval varies    
42 n ― number of time ranges specifications describing the time intervals used to calculate the statistically-processed field 1    
43-46 Total number of data values missing in statistical process 0    
47 Statistical process used to calculate the processed field from the field at each time increment during the time range
  1. 2
  2. 3
  1. maximum
  2. minimum
 
48 Type of time increment between successive fields used in the statistical processing 2 Successive times processed have same start time of forecast, forecast time is incremented.  
49 Indicator of unit of time for time range over which statistical processing is done 1 hour  
50-53 Length of the time range over which statistical processing is done, in units defined by the previous octet 12    
54 Indicator of unit of time for the increment between the successive fields used 1 hour  
55-58 Time increment between successive fields, in units defined by the previous octet 0    

 

wspd / wdir / wgust

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 0 Analysis or forecast at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 2 momentum  
11 Parameter number
  1. 1
  2. 0
  3. 22
  1. Wind Speed
  2. Wind Direction (from which blowing)
  3. Wind Speed (Gust)
 
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground (m)  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 10    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

pop12 / qmd_pop06 / qmd_pop12

octet(s) content value meaning notes
1-4 length of section in octets 71   68 octets have values, but template has room for 71 
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 9 probability forecast at a horizontal level/layer over a continuous time period or time interval  
10 parameter category 1 Moisture  
11 Parameter number 8 Total Precipitation kg m-2; Statistical process 1 (Accumulation) does not change units. It is recommended to use another parameter with "rate" in its name and accumulation in PDT.
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 ground/water surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 forecast probability number 255   pop12
36 total number of forecast probabilities 255   pop12
37 probability type 1 Probability of event above upper limit  
38 scale factor lower limit 4294967169    
39-42 scaled value of lower limit 255    
43 scale factor for upper limit 3    
44-47 scaled value of upper limit 254    
48-49 year (Time of end of overall time interval) varies    
50 month (Time of end of overall time interval) varies    
51 day (Time of end of overall time interval) varies    
52 hour (Time of end of overall time interval) varies    
53 minute (Time of end of overall time interval) varies    
54 second (Time of end of overall time interval) varies    
55 number of time range specifications used to describe the time intervals used to calculate data field varies    
56-59 number of missing values varies    
60 Statistical process used to calculate the processed field from the field at each time increment during the time range 1 accumulation  
61 Type of time increment between successive fields used in the statistical processing 2 Successive times processed have same start time of forecast, forecast time is incremented  
62 Indicator of unit of time for time range over which statistical processing is done 1 hour  
63-66 Length of the time range over which statistical processing is done (units defined by 4.62) 12 or 6    
67 Indicator of unit of time for the increment between the successive fields used 1 hour  
68 Indicator of unit of time for the increment between the successive fields used 0    

 

qpf01 / qpf06 / ppi / pop01 / pop06 / snow01 / snow06 / sleet01 / sleet06 / flatice01 / flatice06 / lineice01 / lineice06 / qmd_qpf06

octet(s) content value meaning notes
1-4 length of section in octets 58    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 8 average accumulation or extreme value  
10 parameter category 1 moisture  
11 Parameter number
  1. 8
  2. 29
  3. 228
  4. 229
  5. 230
  6. 231
  1. Total Precipitation (kg m-2)
  2. Total Snowfall (m)
  3. Flat Ice Accumulation (FRAM) (kg m-2)
  4. Line Ice Accumulation (FRAM) (kg m-2)
  5. Sleet Accumulation (kg m-2)
  6. Precipitation Potential Index
 
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 ground/water surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35-36 year (Time of end of overall time interval) varies    
37 month (Time of end of overall time interval) varies    
38 day (Time of end of overall time interval) varies    
39 hour (Time of end of overall time interval) varies    
40 minute (Time of end of overall time interval) 0    
41 second (Time of end of overall time interval) 0    
42 number of time range specifications used to describe the time intervals used to calculate data field 1    
43-46 number missing 0    
47 Statistical process used to calculate the processed field from the field at each time increment during the time range 1 accumulation  
48 time increment between fields 2 same start time, forecast time is incremented  
49 Indicator of unit of time for time range over which statistical processing is done 1 hour  
50-53 length of time range (units defined in 4.49)

1 or 6

  ppi changes time range from 1 hr to 6 hr after 36 hours
54 time unit for increment between successive fields 1 hour  
55-58 Time increment between successive fields (units defined in 4.54) 0    

 

cig / cldbse

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 6 Cloud  
11 Parameter number 13 Ceiling  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface
  1. 215
  2. 2
  1. Cloud ceiling
  2. Cloud Base Level
 
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

sky

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 6 Cloud  
11 Parameter number 1 Total Cloud Cover  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

vis

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 19 Physical atmospheric properties  
11 Parameter number 0 Visibility  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

WEATHER TYPE

predomwx

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 1 Moisture  
11 Parameter number 226 Predominant Weather  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 0 Reserved   
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

prrain / prfzrn / prsleet / prsnow

octet(s) content value meaning notes
1-4 length of section in octets 47    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 5 probability forecast  
10 parameter category 1 Moisture  
11 Parameter number 19 Precipitation Type  
12 Type of generating process 2    
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 ground/water surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 forecast probability number 1    
36 total number of forecast probabilities 1    
37 probability type 2 probability event between limits (includes lower but not upper limit)  
39-42 scaled value of lower limit varies    
43 scale factor for upper limit 0    
44-47 scaled value of upper limit varies    

 

probiceprsnt

octet(s) content value meaning notes
1-4 length of section in octets 47    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 5 Probability forecasts at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 1 Moisture  
11 Parameter number 232 Probability cloud ice present  
12 Type of generating process 2 Forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 10 entire atmosphere  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 forecast probability number 1    
36 total number of forecast probabilities 1    
37 probability type 3 Probability of event above lower limit  
39-42 scaled value of lower limit varies    
43 scale factor for upper limit 4294967169   this should be checked
44-47 scaled value of upper limit 255    

 

probrefzslt

octet(s) content value meaning notes
1-4 length of section in octets 47    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 5 Probability forecasts at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 1 Moisture  
11 Parameter number 19 Precipitation Type  
12 Type of generating process 2 Forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 10 entire atmosphere  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 forecast probability number 1    
36 total number of forecast probabilities 1    
37 probability type 2 Probability of event between upper and lower limits (the range includes lower limit but no the upper limit)  
38 scale factor lower limit 0    
39-42 scaled value of lower limit varies    
43 scale factor for upper limit 0    
44-47 scaled value of upper limit varies    

 

slrblend

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 1 Moisture  
11 Parameter number 233 Snow Liquid ratio (kg kg-1)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

snowlvl

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 19 Physical atmospheric properties  
11 Parameter number 236 Snow Level (m)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 102 Specific Altitude Above Mean Sea Level  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

mxwbalft

octet(s) content value meaning notes
1-4 length of section in octets 37    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 15 Average, accumulation, extreme values or other statistically-processed values over a spatial area at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 0 temperature  
11 Parameter number 27 Wet Bulb Temperature  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103    
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 610    
29 Type of second fixed surfaced 100    
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 40000    
35 Statistical process used within the spatial area defined by octet 36 255 missing  
36 Type of spatial processing used to arrive at given data value from source data 255 missing  
37 Number of data points used in spatial processing defined in octet 36 255 missing   

 

THUNDERSTORMS

ptstm01 / ptstm03 / ptsm12

octet(s) content value meaning notes
1-4 length of section in octets 58    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 8 Average, accumulation, extreme values or other statistically processed values at a horizontal level or in a horizontal layer in a continuous or non-continuous time interval  
10 parameter category 19 Physical atmospheric properties  
11 Parameter number 2 Thunderstorm Probability  
12 Type of generating process 5 Probability Forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 96 "Global Forecast System Model
T1534 - Forecast hours 00-384
T574 - Forecast hours 00-192
T190 - Forecast hours 204-384"
 
15-16 Hours after reference time data cutoff 66535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35-36 Year ― Time of end of overall time interval varies    
37 Month - Time of end of overall time interval varies    
38 Day - Time of end of overall time interval varies    
39 Hour - Time of end of overall time interval varies    
40 Minute - Time of end of overall time interval varies    
41 Second - Time of end of overall time interval varies    
42 n ― number of time ranges specifications describing the time intervals used to calculate the statistically-processed field 1    
43-46 Total number of data values missing in statistical process 0    
47 Statistical process used to calculate the processed field from the field at each time increment during the time range 1 Accumulation   The original data value (Y in the note 4 of regulation 92.9.4) has units of Code table 4.2 multiplied by second, unless otherwise noted on Code table 4.2.
48 Type of time increment between successive fields used in the statistical processing 2 Successive times processed have same start time of forecast, forecast time is incremented.  
49 Indicator of unit of time for time range over which statistical processing is done 1 hour  
50-53 Length of the time range over which statistical processing is done, in units defined by the previous octet 1/3/12    
54 Indicator of unit of time for the increment between the successive fields used 255 missing  
55-58 Time increment between successive fields, in units defined by the previous octet 255 missing  

 

dryts03

octet(s) content value meaning notes
1-4 length of section in octets 71   68 octets have values, but template has room for 71 
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 9 probability forecast at a horizontal level/layer over a continuous time period or time interval  
10 parameter category 19 Physical atmospheric properties  
11 Parameter number 237 Dry Thunderstorm Probability (%)  
12 Type of generating process 5 Probability Forecast  
13 Background generating process identifier 0    
14 Forecast generating process identified 113 Products from NCEP SREF processing  
15-16 Hours after reference time data cutoff 0    
17 Minutes after reference time data cutoff 0    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 ground/water surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 forecast probability number 0    
36 total number of forecast probabilities 21    
37 probability type 1 Probability of event above upper limit  
38 scale factor lower limit 0    
39-42 scaled value of lower limit 0    
43 scale factor for upper limit 0    
44-47 scaled value of upper limit 0    
48-49 year (Time of end of overall time interval) varies    
50 month (Time of end of overall time interval) varies    
51 day (Time of end of overall time interval) varies    
52 hour (Time of end of overall time interval) varies    
53 minute (Time of end of overall time interval) varies    
54 second (Time of end of overall time interval) varies    
55 number of time range specifications used to describe the time intervals used to calculate data field varies    
56-59 number of missing values varies    
60 Statistical process used to calculate the processed field from the field at each time increment during the time range 1 accumulation  
61 Type of time increment between successive fields used in the statistical processing 2 Successive times processed have same start time of forecast, forecast time is incremented  
62 Indicator of unit of time for time range over which statistical processing is done 1 hour  
63-66 Length of the time range over which statistical processing is done (units defined by 4.62) 3    
67 Indicator of unit of time for the increment between the successive fields used 255    
68 Indicator of unit of time for the increment between the successive fields used 0    

 

posengy

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 7 Thermodynamic Stability indicies  
11 Parameter number 202 Bourgoiun Positive Energy Layer (2k ft AGL to 400 hPa) J kg-1  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 610    
29 Type of second fixed surfaced 100    
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 40000    

 

negengy

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 7 Thermodynamic Stability indicies  
11 Parameter number 201 Bourgoiun Negative Energy Layer (surface to freezing level) (J kg-1)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 4 Level of 0 degree C Isotherm  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

echotop

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0    
10 parameter category 16 Forecast Radar Imagery  
11 Parameter number

3

Echo Top For Echo Top product, Use octet number 38 to store threshold value (for example, 18.3 dB) in Product Definition Template 4.20. See Template 4.20.
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 3 Level of Cloud Tops  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

maxref

octet(s) content value meaning notes
1-4 length of section in octets 58    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 8 average accumulation or extreme value  
10 parameter category 16 Forecast Radar Imagery  
11 Parameter number 198 Hourly Maximum of Simulated Reflectivity at 1 km AGL (dB)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground (m)  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 1000    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35-36 year (Time of end of overall time interval) varies    
37 month (Time of end of overall time interval) varies    
38 day (Time of end of overall time interval) varies    
39 hour (Time of end of overall time interval) varies    
40 minute (Time of end of overall time interval) 0    
41 second (Time of end of overall time interval) 0    
42 number of time range specifications used to describe the time intervals used to calculate data field 1    
43-46 number missing 0    
47 Statistical process used to calculate the processed field from the field at each time increment during the time range 2 Maximum  
48 time increment between fields 2 Successive times processed have same start time of forecast, forecast time is incremented  
49 Indicator of unit of time for time range over which statistical processing is done 1 hour  
50-53 length of time range (units defined in 4.49) 1    
54 time unit for increment between successive fields 1 hour  
55-58 Time increment between successive fields (units defined in 4.54) 0    

 

vil

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 15 Radar  
11 Parameter number

3

Vertically-Integrated Liquid Water (kg m-2)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 10 Entire Atmosphere  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

BOUNDARY LAYER AND FIRE WEATHER

llwsspd / llwsdir 

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 0 Analysis or forecast at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 2 Momentum  
11 Parameter number
  1. 0
  2. 1
  1. Wind Direction (from which blowing)
  2. Wind Speed (m s-1)
 
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 103 Specified Height Level Above Ground (m)  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 610    

 

llwshhgt

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 0 Analysis or forecast at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 3 Mass  
11 Parameter number 6 Geometric Height (m)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 103 Specified Height Level Above Ground (m)  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 610    

 

mixhgt

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 0    
10 parameter category 19 Physical atmospheric properties  
11 Parameter number 3 Mixed Layer Depth (m)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 200 Entire atmosphere (considered as a single layer)  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

trwspd / trwdir / vrate 

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 0    
10 parameter category 2 Momentum  
11 Parameter number
  1. 224
  2. 225
  3. 226
  1. Ventilation Rate (m2s-1)
  2. Transport Wind Speed (m s-1)
  3. Transport Wind Direction (degrees)
 
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 200 Entire atmosphere (considered as a single layer)  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

maxhi

octet(s) content value meaning notes
1-4 length of section in octets 58    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 8 average accumulation or extreme value  
10 parameter category 4 Fire weather Discipline=2 (IS0.7)
11 Parameter number

2

Haines Index Discipline=2 (IS0.7)
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 200 Entire atmosphere (considered as a single layer)  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35-36 year (Time of end of overall time interval) varies    
37 month (Time of end of overall time interval) varies    
38 day (Time of end of overall time interval) varies    
39 hour (Time of end of overall time interval) varies    
40 minute (Time of end of overall time interval) 0    
41 second (Time of end of overall time interval) 0    
42 number of time range specifications used to describe the time intervals used to calculate data field 1    
43-46 number missing 0    
47 Statistical process used to calculate the processed field from the field at each time increment during the time range 2 Maximum  
48 time increment between fields 2 same start time, forecast time is incremented  
49 Indicator of unit of time for time range over which statistical processing is done 1 hour  
50-53 length of time range (units defined in 4.49) 6    
54 time unit for increment between successive fields 1 hour  
55-58 Time increment between successive fields (units defined in 4.54) 0    

 

maxffwi

octet(s) content value meaning notes
1-4 length of section in octets 58    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 8 average accumulation or extreme value  
10 parameter category 4 Fire Weather  
11 Parameter number

4

Fosberg Index The Fosberg index denotes the potential influence of weather on a wild and fire. It takes into account the combined effects of temperature, wind speed, relative humidity and precipitation. Higher values indicate a higher potential impact
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 ground/water surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 2    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35-36 year (Time of end of overall time interval) varies    
37 month (Time of end of overall time interval) varies    
38 day (Time of end of overall time interval) varies    
39 hour (Time of end of overall time interval) varies    
40 minute (Time of end of overall time interval) 0    
41 second (Time of end of overall time interval) 0    
42 number of time range specifications used to describe the time intervals used to calculate data field 1    
43-46 number missing 0    
47 Statistical process used to calculate the processed field from the field at each time increment during the time range 2 Maximum  
48 time increment between fields 2 same start time, forecast time is incremented  
49 Indicator of unit of time for time range over which statistical processing is done 1 hour  
50-53 length of time range (units defined in 4.49) 6    
54 time unit for increment between successive fields 1 hour  
55-58 Time increment between successive fields (units defined in 4.54) 0    

 

WATER SURFACE ELEMENTS

sigwv

octet(s) content value meaning notes
1-4 length of section in octets 34    
5 section number 4    
6-7 Number of coordinate values after template 0 no vertical discretization has occured for this data  
8-9 product template 0 analysis/forecast at a horizontal level/layer at a point in time  
10 parameter category 0 Waves Discipline=10 (IS0.7)
11 Parameter number Significant Height of Combined Wind Waves and Swell (m) Discipline=10 (IS0.7)
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    

 

CDF Products

Oceanic Wind Speed / Wind Gust (CDF)

octet(s) content value meaning notes
1-4 length of section in octets 35    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 6 Percentile forecasts at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 2 Momentum  
11 Parameter number
  1. 1
  2. 22
  1. Wind Speed (m s-1)
  2. Wind Speed (Gust) (m s-1)
 
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hours  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 10, 30 or 80    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 Percentile value (from 100% to 0%) speed:
  • 10
  • 25
  • 50
  • 75
  • 90
gust:
  • 50
  indicated in file name: cdf-p[this]

 

Oceanic MSLP (CDF)

octet(s) content value meaning notes
1-4 length of section in octets 35    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 6 Percentile forecasts at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 3 Mass  
11 Parameter number 1 Pressure Reduced to MSL (Pa)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hours  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 101 Mean Sea Level  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 Percentile value (from 100% to 0%)
  • 10
  • 50
  • 90
  indicated in file name: cdf-p[this]

 

Oceanic temp (CDF)

octet(s) content value meaning notes
1-4 length of section in octets 35    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 6 Percentile forecasts at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 0 Temperature  
11 Parameter number 0 Temperature  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hours  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 103 Specified Height Level Above Ground  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 2    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 Percentile value (from 100% to 0%) 50   indicated in file name: cdf-p[this]

 

Oceanic vis (CDF)

octet(s) content value meaning notes
1-4 length of section in octets 35    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 6 Percentile forecasts at a horizontal level or in a horizontal layer at a point in time  
10 parameter category 19 Physical atmospheric properties  
11 Parameter number 0 Visibility   
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hours  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 Ground or Water Surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 Percentile value (from 100% to 0%) 50   indicated in file name: cdf-p[this]

 

Probabilistic

qmd_qpf06p10 / qmd_qpf06p50 / qmd_qpf06p90

octet(s) content value meaning notes
1-4 length of section in octets 59    
5 section number 4    
6-7 Number of coordinate values after template 0    
8-9 product template 10    
10 parameter category 1 Moisture  
11 Parameter number 8 Total precipitation (kg m-2)  
12 Type of generating process 2 forecast  
13 Background generating process identifier 255    
14 Forecast generating process identified 104 National Blend GRIB  
15-16 Hours after reference time data cutoff 65535    
17 Minutes after reference time data cutoff 255    
18 Indicator of unit of time range 1 hour  
19-22 Forecast time (units defined by 4.18) varies    
23 Type of first fixed surface 1 ground or water surface  
24 Scale factor of first fixed surface 0    
25-28 Scaled value of first fixed surface 0    
29 Type of second fixed surfaced 255 missing  
30 Scale factor of second fixed surface 0    
31-34 Scaled value of second fixed surfaces 0    
35 Percentile value (from 100% to 0%)
  • 10
  • 50
  • 90
   
36-37 Year ― Time of end of overall time interval varies    
38 Month - Time of end of overall time interval varies    
39 Day - Time of end of overall time interval varies    
40 Hour - Time of end of overall time interval varies    
41 Minute - Time of end of overall time interval varies    
42 Second - Time of end of overall time interval varies    
43 n ― number of time ranges specifications describing the time intervals used to calculate the statistically-processed field 1    
44-47 Total number of data values missing in statistical process 0    
48 Statistical process used to calculate the processed field from the field at each time increment during the time range 1 Accumulation  
49 Type of time increment between successive fields used in the statistical processing 2 Successive times processed have same start time of forecast, forecast time is incremented.  
50 Indicator of unit of time for time range over which statistical processing is done 1 hour  
51-54 Length of the time range over which statistical processing is done, in units defined by the previous octet 6    
55 Indicator of unit of time for the increment between the successive fields used 1 hour  
56-59 Time increment between successive fields, in units defined by the previous octet 0    

 

IS5: Data Representation Section

Section 5 defines the how the data is calculated and packed. Some grib2 octets will vary by run; these can be read with a program such as degrib. Elements with similar grib2 properties have been grouped. There are currently the following groups:

 

Standard (all except dryts03/predomwx)

octet(s) content value meaning notes
1-4 length of section in octets 49    
5 section number 5    
6-9 "Number of data points where one or more values are specified in Section 7 when a bit map is present; total number of data points when a bit map is absent" varies by grid (see IS3)   3744965 (co); 1822145(ak); 76275(pr); 350625(hi); 4573389(oc)
10-11 template number 3 Grid Point Data - Complex Packing and Spatial Differencing  
12-15 Reference value (R) (IEEE 32-bit floating-point value) varies    
16-17 Binary scale factor (E) varies   usually stable by element:
  • vis vis-cdf=7;
  • cig cldbse snowlevel llwshgt mixhgt vrate=3;
  • appt dewp mxwbalft temp wgust wspd llwspd trwspd echotop maxref maxffwi gust-cdf temp-cdf wspd-cdf=2;
  • all others=0
18-19 Decimal scale factor (D) varies   usually 0-4; wdir llwsdir trwdir mslp-cdf=4294967295
20 Number of bits used for each packed value for simple packing, or for each group reference value for complex packing or spatial differencing varies    
21 Type of original field values 0 Floating Point  
22 Group splitting method used 1 General Group Splitting  
23 Missing value management used 1 Primary missing values included within the data values  
24-27 Primary missing value substitute 9999    
28-31 Secondary missing value substitute 0    
32-35 NG ― number of groups of data values into which field is split varies    
36 Reference for group widths varies   usually 0 - 1
37 Number of bits used for the group widths (value after - oct 5.36) varies    
38-41 Reference for group lengths 1   may vary; probrefzslt has value 2147483647 instead of 1
42 Length increment for the group lengths 1   may vary
43-46 True length of last group varies    
47 Number of bits used for the scaled group lengths (after - oct5.38 and % by oct5.42) varies    
48 Order of spatial difference 2 Second-Order Spatial Differencing  
49 Number of octets required in the data section to specify extra descriptors needed for spatial differencing (octets 6-ww in data template 7.3) varies   usually 1-3

dryts03

octet(s) content value meaning notes
1-4 length of section in octets 21    
5 section number 5    
6-9 "Number of data points where one or more values are specified in Section 7 when a bit map is present; total number of data points when a bit map is absent" 2496141   does not match other elements with conus grid
10-11 template number 0 Grid Point Data - Complex Packing and Spatial Differencing  
12-15 Reference value (R) (IEEE 32-bit floating-point value) varies    
16-17 Binary scale factor (E) 0   may vary
18-19 Decimal scale factor (D) 0   may vary
20 Number of bits used for each packed value for simple packing, or for each group reference value for complex packing or spatial differencing varies    
21 Type of original field values 0 Floating Point  

 

predomwx

octet(s) content value meaning notes
1-4 length of section in octets 47    
5 section number 5    
6-9 Number of data points where one or more values are specified in Section 7 when a bit map is present; total number of data points when a bit map is absent varies by grid (see IS3)   3744965 (co); 1822145(ak);
10-11 template number 2 Grid Point Data - Complex Packing  
12-15 Reference value (R) (IEEE 32-bit floating-point value) varies    
16-17 Binary scale factor (E) 0   may vary
18-19 Decimal scale factor (D) varies   usually 0-1
20 Number of bits used for each packed value for simple packing, or for each group reference value for complex packing or spatial differencing varies    
21 Type of original field values 0 Floating Point  
22 Group splitting method used 1 General Group Splitting  
23 Missing value management used 1 Primary missing values included within the data values  
24-27 Primary missing value substitute 9999    
28-31 Secondary missing value substitute 0    
32-35 NG ― number of groups of data values into which field is split varies    
36 Reference for group widths 1   The group width is the number of bits used for every value in a group
37 Number of bits used for the group widths (after the reference value in octet 36 has been removed) 3    
38-41 Reference for group lengths 1   The group length (L) is the number of values in a group.
42 Length increment for the group lengths 1   The essence of the complex packing method is to subdivide a field of values into NG groups, where the values in each group have similar sizes. In this procedure, it is necessary to retain enough information to recover the group lengths upondecoding. The NG group lengths for any given field can be described by Ln = ref + Kn x len_inc, n = 1,NG, where ref is given by octets 38 - 41 and len_inc by octet 42. The NG values of K (the scaled group lengths) are stored in the data section, each with the number of bits specified by octet 47. Since the last group is a special case which may not be able to be specified by this relationship, the length of the last group is stored in octets 43-46.
43-46 True length of last group varies    
47 Number of bits used for the scaled group lengths (after subtraction of the reference value given in octets 38-41 and division by the length increment given in octet 42) varies    

IS6: Bit Map Section

IS6 Groups

Section 6 defines the how the data uses a bitmap. Some grib2 octets will vary by run; these can be read with a program such as degrib. Elements with similar grib2 properties have been grouped. There are currently the following groups:

Standard (all except dryts03)

octet(s) content value meaning notes
1-4 length of section in octets 6    
5 section number 6    
6 bitmap indicator 255 A bit map does not apply to this product  

dryts03

octet(s) content value meaning notes
1-4 length of section in octets 468127    
5 section number 6    
6 bitmap indicator 0 A bit map applies to this product and is specified in this section  
7+   0   All values = 0 

IS7: Data Section

IS7 Groups

Section 7 houses data. Some grib2 octets will vary by run; these can be read with a program such as degrib. Elements with similar grib2 properties have been grouped. There are currently the following groups:

Standard

octet(s) content value meaning notes
1-4 length of section in octets varies    
5 section number 7    
6+ data 0   in a format described by data Template 7.X, where X is the data representation template number in octet 5.10

IS8: End Section

All

octet(s) content value meaning notes
1-4   7777 [END] Coded according to the International Alphabet Number 5.

NBM