Navigation Links


Products Guide

QPE-to-FFG Ratio

QPE-to-FFG Ratio

Short Description

Analogous to the ratio provided in FFMP, this is the ratio of the current MRMS Radar-Only QPE value at each grid point to the current nationally-mosaicked FFG value for the same grid point.


Available for rainfall durations of 1-, 3-, and 6-hours.  A maximum product exists which finds the maximum ratio across all accumulation durations.

Primary Users


Input Sources

MRMS Radar-Only QPE, and Nationally-Mosaicked FFG


Spatial:  ~1 km x 1 km

Temporal:  2 minutes (Keep in mind FFG only updated every 6 hours)

Product Creation

The FLASH system takes the MRMS Radar-Only QPE value for the defined accumulation periods (1-, 3-, and 6-hours) and compares those gridded values to the corresponding nationally-mosaicked FFG gridded values. 

Technical Details

Latest Update: MRMS Version 12

NOTE: In version 12, all FLASH products now use the instantaneous rainfall rates from the Dual-pol radar synthetic QPE product.


Gourley, J., Z. Flamig, H. Vergara, P. Kirstetter, R. Clark III, E. Argyle, A. Arthur, S. Martinaitis, G. Terti, J. Erlingis, Y. Hong, and K. Howard, 2016: The Flooded Locations And Simulated Hydrographs (FLASH) project: improving the tools for flash flood monitoring and prediction across the United States. Bull. Amer. Meteor. Soc. doi:10.1175/BAMS-D-15-00247.1, in press.