M-2 Flash Flood Watch

Time: 904 AM Thu July 1, 2021 Forecaster: Brad Simmons ------------------------- MESSAGE 2 Flash Flood Prediction Program ------------------------- FLASH FLOOD WATCH The National Weather Service has issued a FLASH FLOOD WATCH for: the following counties: BOULDER (CITY OF BOULDER AFFECTED, FOUR MILE BURN AREA AFFECTED), JEFFERSON, BROOMFIELD, DOUGLAS, ADAMS, DENVER, ARAPAHOE including: DIA, THE CITY OF AURORA, ARVADA, WHEAT RIDGE, LAKEWOOD ------------------------------------------------------------------------------ from: 1100 AM to 1159 PM . THE NATIONAL WEATHER SERVICE IN BOULDER HAS ISSUED A FLASH FLOOD WATCH FOR ALL AREAS OF THE DISTRICT AND IS VALID FROM 11AM TO MIDNIGHT. Prime time for flooding: 100 PM to 900 PM . ------------------------------------------------------------------------------ Forecast rainfall: Thunderstorms will have the potential to produce rainfall rates of 0.6-1.8" in 10-30 minutes. Training of thunderstorm cells or a large slow moving strong thunderstorm may result in very heavy rainfall of up to 4.0" in 60-90 minutes. Should rain continue for longer than 90 minutes in duration higher amounts are possible. ------------------------------------------------------------------------------ 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 anchor briefly and multiple thunderstorms will have the potential to train over the same area this afternoon and evening which may result in extended periods of heavy rainfall and flash flooding. A Flash Flood Watch means that flash flooding is possible within the watch area. 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]