The Global Forecast System

The Global Forecast System (GFS) is a global numerical weather prediction system containing a global computer model and variational analysis run by the U.S. National Weather Service (NWS).

The mathematical model is run four times a day, and produces forecasts for up to 16 days in advance, with decreased spatial resolution after 10 days. The model is a spectral model with a resolution of T1534 from 0 to 240 hours (0-10 days) and T574 from 240 to 384 hours (10-16 days). In the vertical, the model is divided into 64 layers and temporally, it produces forecast output every hour for the first 12 hours, every 3 hours out to 10 days, and every 12 hours after that.


Contacts:

Modeling and Data Assimilation Branch - Vijay Tallapragada

Website and Experiment Help - Kate Howard

Recent Implementations & RFCs

RFC 4060 - global_shared v14.1.2

On WCOSS, switched operational assimilation of GOES-E AMVs (Atmospheric Motion Vectors) from GOES-13 to GOES-16. Implemented on January 5 at 1400Z.

RFC 4002 - GFS related (obsproc_satingest v3.4.2, obsproc_global v3.1.0, bufr_dumplist v1.5.0)

Several changes being made on WCOSS to start monitoring GOES-16 data in the GFS/GDAS models:

  • Changes to obs processing satellite ingest package and related packages to ingest GOES-16 data into WCOSS data tanks.
  • Update GDAS/GFS to begin monitoring GOES-16 data. A follow-on RFC will be submitted to change from monitor mode to assimilation mode in early January.

Separately, but included in this release, we will begin alerting ‘gfs.tCCz.nstanl.nemsio’ and ‘gdas.tCCz.nstanl.nemsio’, per a request from NCO/IDSB/Dataflow. To be implemented on December 18 at 1400Z.


Click here or on "RFCS" above to see full RFC list.

Future Implementation Plans

Planned for FY18/19: FV3GFS

Click on "Implementations" above for more information.