Flash Flood Prediction Program

Time: 819 PM Tue July 6, 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 midnight tonight. - Thunderstorms have developed over western areas of the District and are expected to become more numerous over the coming hours. Strong thunderstorms will be capable of producing heavy rainfall that may lead to excessive runoff and possibly flash flooding. - Best chances for stronger storms will be W of I-25 and S of I-70 with a lesser chance for stronger storms further away from the foothills over the NE quadrant of the District. Storms will move from NNW to SSE at 10-15mph. Best chances for thunderstorms will be through 11pm. STORM RAINFALL POTENTIAL AND DURATION: Moderate to strong thunderstorms will have the potential to produce 0.3-0.9" of rain in 10-30 minutes. WORST CASE SCENARIO: A strong, slow moving thunderstorm may result in up to 1.6" of heavy rain in 45-60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Lakewood 1 Current TO 1159 PM Current TO 1100 PM Wheat Ridge 1 Current TO 1159 PM Current TO 1100 PM Arvada 1 Current TO 1159 PM Current TO 1100 PM the City of Aurora 1 Current TO 1159 PM Current TO 1100 PM Arapahoe County 1 Current TO 1159 PM Current TO 1100 PM DIA 1 Current TO 1159 PM Current TO 1100 PM Denver County 1 Current TO 1159 PM Current TO 1100 PM Adams County 1 Current TO 1159 PM Current TO 1100 PM Douglas County 1 Current TO 1159 PM Current TO 1100 PM Broomfield County 1 Current TO 1159 PM Current TO 1100 PM Jefferson County 1 Current TO 1159 PM Current TO 1100 PM Boulder County 1 Current TO 1159 PM Current TO 1100 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1159 PM TUE 0.1" (60%) to 0.4" (30%) to 0.9" (15%) ISSUED Arapahoe Current TO 1159 PM TUE 0.1" (80%) to 0.4" (50%) to 0.9" (25%) ISSUED Boulder Current TO 1159 PM TUE 0.1" (95%) to 0.4" (65%) to 0.9" (30%) ISSUED Broomfield Current TO 1159 PM TUE 0.1" (80%) to 0.4" (50%) to 0.9" (25%) ISSUED Denver Current TO 1159 PM TUE 0.1" (80%) to 0.4" (50%) to 0.9" (25%) ISSUED Douglas Current TO 1159 PM TUE 0.1" (95%) to 0.4" (65%) to 0.9" (30%) ISSUED Jefferson Current TO 1159 PM TUE 0.1" (95%) to 0.4" (65%) to 0.9" (30%) ISSUED Foothills above 6500ft       Boulder Current TO 1159 PM TUE 0.1" (100%) to 0.4" (75%) to 0.9" (40%) ISSUED Douglas Current TO 1159 PM TUE 0.1" (100%) to 0.4" (75%) to 0.9" (40%) ISSUED Jefferson Current TO 1159 PM TUE 0.1" (100%) to 0.4" (75%) to 0.9" (40%) 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]