Time: 1057 AM Thu August 19, 2021 Forecaster: Brad Simmons ------------------------- MESSAGE 1 Flash Flood Prediction Program ------------------------- STREET FLOODING POTENTIAL We have determined that street and small stream flooding is possible in the following counties: BOULDER (CITY OF BOULDER AFFECTED, FOUR MILE BURN AREA AFFECTED), JEFFERSON, BROOMFIELD, ADAMS, DENVER, ARAPAHOE including: DIA, THE CITY OF AURORA, ARVADA, WHEAT RIDGE, LAKEWOOD ------------------------------------------------------------------------------ from: Current to 600 PM . Prime time for flooding: 1200 PM to 500 PM . ------------------------------------------------------------------------------ Forecast rainfall: Moderate to strong thunderstorms will have the potential to produce 0.2-0.6" of heavy rain in 10-20 minutes. Training of moderate to strong thunderstorm cells may result in up to 1.8" in 40-60 minutes. ------------------------------------------------------------------------------ The most likely areas to be impacted by flooding are: X Mountain streams & floodplains; road crossings; canyon roads & highways; recreational trails; adjacent open space areas/campgrounds/parks; fishing access points & stream reaches; buildings near streams; utilities X Urban streams/gulches; road crossings; recreational trails; adjacent open space areas/campgrounds/parks; floodplain properties; utilities X Urban streets, intersections, low lying areas, known trouble spots X Mountain locations subject to mud/rock/debris slide ------------------------------------------------------------------------------ Additional Information: Strong thunderstorms may also contain large hail, gusty winds and frequent cloud-to-ground lightning. This message is not intended for public dissemination. Please pass this information along to affected emergency response organizations (police, fire, public works, etc.) within your area. Also, please take appropriate actions to prepare for possible flooding. Further information will be provided to you as it becomes available. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]