Flash Flood Prediction Program

Time: 349 PM Wed August 14, 2024 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1’S HAVE BEEN ISSUED FOR THE ENTIRE DISTRICT EFFECTIVE UNTIL 10:00 PM A gust front from the northeast has moved into the District this afternoon resulting in a few strong storms to develop over portions of the District. Some of these storms contain large hail and moderate to brief heavy rain. The biggest threat from these storms will be a quick 0.5” in 10-20 minutes, rather than any long-lasting rainfall. Storms are generally moving west to east with erratic storm motions likely along gust fronts. These erratic storms will have the best chance for Low Impact Flooding as heavy rainfall likely to stall over some areas. Storms will likely be off and on through the rest of the afternoon and into the evening hours. Skies will gradually clear after 10pm with clearing skies overnight. A few areas of fog in the morning will be possible as overnight temperatures drop into the low 60s on the plains with mid 50s along the foothills. STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms will produce rainfall rates of 0.1-0.4” total in 10-30 minutes. Strong to severe thunderstorms will have the potential to produce rainfall rates of 0.4-0.8” total of rain in 10-30 minutes. WORST CASE SCENARIO: A slow-moving strong thunderstorm or a large thunderstorm complex may result in up to 1.5” of rain in 45-60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Lakewood 1 Current TO 1000 PM Current TO 900 PM Wheat Ridge 1 Current TO 1000 PM Current TO 900 PM the City of Aurora 1 Current TO 1000 PM Current TO 900 PM Arvada 1 Current TO 1000 PM Current TO 900 PM Arapahoe County 1 Current TO 1000 PM Current TO 900 PM DIA 1 Current TO 1000 PM Current TO 900 PM Adams County 1 Current TO 1000 PM Current TO 900 PM Denver County 1 Current TO 1000 PM Current TO 900 PM Douglas County 1 Current TO 1000 PM Current TO 900 PM Broomfield County 1 Current TO 1000 PM Current TO 900 PM Jefferson County 1 Current TO 1000 PM Current TO 900 PM Boulder County 1 Current TO 1000 PM Current TO 900 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1000 PM WED 0.1" (60%) to 0.4" (40%) to 0.8" (20%) ISSUED Arapahoe Current TO 1000 PM WED 0.1" (60%) to 0.4" (40%) to 0.8" (20%) ISSUED Boulder Current TO 1000 PM WED 0.1" (60%) to 0.4" (40%) to 0.8" (20%) ISSUED Broomfield Current TO 1000 PM WED 0.1" (60%) to 0.4" (40%) to 0.8" (20%) ISSUED Denver Current TO 1000 PM WED 0.1" (60%) to 0.4" (40%) to 0.8" (20%) ISSUED Douglas Current TO 1000 PM WED 0.1" (60%) to 0.4" (40%) to 0.8" (20%) ISSUED Jefferson Current TO 1000 PM WED 0.1" (60%) to 0.4" (40%) to 0.8" (20%) ISSUED Foothills above 6500ft       Boulder Current TO 1000 PM WED 0.1" (40%) to 0.4" (30%) to 0.8" (10%) ISSUED Douglas Current TO 1000 PM WED 0.1" (50%) to 0.4" (40%) to 0.8" (20%) ISSUED Jefferson Current TO 1000 PM WED 0.1" (40%) to 0.4" (30%) 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]