Time: 107 PM Tue August 3, 2021 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S ISSUED FOR THE ENTIRE DISTRICT - Message 1's have been issued for the entire District and will be valid until 10pm this evening. - Thunderstorms are expected to develop over the coming hours and will be capable of producing heavy rainfall later this afternoon and evening. Prime time for stronger thunderstorms is from 3-9pm. Thunderstorms will be slow moving and may result in extended periods of heavy rain that may lead to excessive runoff and possibly flash flooding. - Stronger storms today may favor areas S of I-70 and E of Hwy 85 as there has been more sunshine and more heating through early afternoon to fuel storms in this area. STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak thunderstorms will produce 0.1-0.5" in 10-30 minutes. Moderate to strong thunderstorms will have the potential to produce 0.5-1.5" of heavy rain in 10-30 minutes. WORST CASE SCENARIO: A stationary strong thunderstorm may result in up to 2.5" in 45-60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Broomfield County 1 Current TO 1000 PM 300 PM TO 900 PM Lakewood 1 Current TO 1000 PM 300 PM TO 900 PM Wheat Ridge 1 Current TO 1000 PM 300 PM TO 900 PM Arvada 1 Current TO 1000 PM 300 PM TO 900 PM the City of Aurora 1 Current TO 1000 PM 300 PM TO 900 PM Arapahoe County 1 Current TO 1000 PM 300 PM TO 900 PM DIA 1 Current TO 1000 PM 300 PM TO 900 PM Denver County 1 Current TO 1000 PM 300 PM TO 900 PM Adams County 1 Current TO 1000 PM 300 PM TO 900 PM Douglas County 1 Current TO 1000 PM 300 PM TO 900 PM Jefferson County 1 Current TO 1000 PM 300 PM TO 900 PM Boulder County 1 Current TO 1000 PM 300 PM TO 900 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 300 PM TO 1000 PM 0.1" (95%) to 0.5" (50%) to 1.5" (25%) ISSUED Arapahoe 300 PM TO 1000 PM 0.1" (95%) to 0.5" (65%) to 1.5" (35%) ISSUED Broomfield 300 PM TO 1000 PM 0.1" (90%) to 0.5" (40%) to 1.5" (20%) ISSUED Denver 300 PM TO 1000 PM 0.1" (95%) to 0.5" (50%) to 1.5" (25%) ISSUED Boulder 200 PM TO 1000 PM 0.1" (90%) to 0.5" (40%) to 1.5" (20%) ISSUED Douglas 200 PM TO 1000 PM 0.1" (100%) to 0.5" (65%) to 1.5" (35%) ISSUED Jefferson 200 PM TO 1000 PM 0.1" (90%) to 0.5" (50%) to 1.5" (25%) ISSUED Foothills above 6500ft       Boulder 100 PM TO 1000 PM 0.1" (90%) to 0.5" (40%) to 1.5" (20%) ISSUED Douglas 100 PM TO 1000 PM 0.1" (100%) to 0.5" (65%) to 1.5" (35%) ISSUED Jefferson 100 PM TO 1000 PM 0.1" (100%) to 0.5" (65%) to 1.5" (35%) 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]