Flash Flood Prediction Program

Time: 405 PM Sat May 29, 2021 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S CONTINUE VALID FOR THE DISTRICT - Message 1's will continue valid for the entire District through 10pm this evening although the threat for heavy rainfall is lowering. - An initial thunderstorm over Jefferson County early this afternoon produced cloud cover over the District keeping temperatures lower than surrounding locations and has resulted in a lack of storms so far today as the air has remained rather stable. Additional daytime heating or outflow from thunderstorms to the S and N of the District may be able to initiate new thunderstorms over the coming hours that would be capable of heavy rainfall as ample surface moisture remains in place. - Around sunset the threat for thunderstorms will diminish and Messages will most likely be allowed to expire this evening. STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms will produce 0.1-0.3" of rain in 10-30 minutes. Strong thunderstorms will have the potential to produce 0.3-0.8" in 10-30 minutes. WORST CASE SCENARIO: Training of thunderstorm cells or a large/slower moving thunderstorm may result in up to 1.6" of rain in 45-60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Douglas County 1 Current TO 1000 PM 100 PM TO 900 PM Broomfield County 1 Current TO 1000 PM 100 PM TO 900 PM Jefferson County 1 Current TO 1000 PM 100 PM TO 900 PM Boulder County 1 Current TO 1000 PM 100 PM TO 900 PM Adams County 1 Current TO 1000 PM 100 PM TO 900 PM Denver County 1 Current TO 1000 PM 100 PM TO 900 PM DIA 1 Current TO 1000 PM 100 PM TO 900 PM Arapahoe County 1 Current TO 1000 PM 100 PM TO 900 PM the City of Aurora 1 Current TO 1000 PM 100 PM TO 900 PM Arvada 1 Current TO 1000 PM 100 PM TO 900 PM Wheat Ridge 1 Current TO 1000 PM 100 PM TO 900 PM Lakewood 1 Current TO 1000 PM 100 PM TO 900 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1000 PM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (10%) ISSUED Arapahoe Current TO 1000 PM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (10%) ISSUED Boulder Current TO 1000 PM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (10%) ISSUED Broomfield Current TO 1000 PM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (10%) ISSUED Denver Current TO 1000 PM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (10%) ISSUED Douglas Current TO 1000 PM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (10%) ISSUED Jefferson Current TO 1000 PM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (10%) ISSUED Foothills above 6500ft       Boulder Current TO 1000 PM SAT 0.1" (75%) to 0.3" (40%) to 0.8" (10%) ISSUED Douglas Current TO 1000 PM SAT 0.1" (75%) to 0.3" (40%) to 0.8" (10%) ISSUED Jefferson Current TO 1000 PM SAT 0.1" (75%) to 0.3" (40%) to 0.8" (10%) ISSUED MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]