Evaluating the Impact of MRMS Updates on the Quantitative Precipitation Estimates for FLASH Hydrologic Modeling Products

This contribution will present an evaluation of the impact of updated Quantitative Precipitation Estimates (QPEs) from the Multi-Radar Multi-Sensor (MRMS) system on the hydrologic modeling skill of the Flooded Locations And Simulated Hydrographs (FLASH) suite. FLASH is a sub-component of MRMS that generates hydrometeorological products used for flash flood warning operations in the US National Weather Service (NWS). FLASH has been running at the National Center for Environmental Prediction (NCEP) since November of 2016 and added to the Satellite Broadcast Network (SBN) system in early 2021. Since its transition into operations in 2014, MRMS’s QPE products have been enhanced through a series of algorithm updates including a dual-polarization synthetic radar QPE that replaced the reflectivity-only approach. To date, the only formal evaluation of the hydrologic models running within FLASH has been done with a reanalysis of MRMS QPEs covering the 2002-2011 period. While the results of this past study have provided an insightful picture of the skill of FLASH peak flow simulation and expected uncertainty, this new assessment of FLASH hydrologic outputs focusing on the 2019 – present period will shed some light into potential improvements for flash flood warning operations due to QPE enhancements.