Flash Flood Prediction Program

Time: 926 AM Wed August 21, 2024 Forecaster: Laura Smith ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- Isolated to Scattered Storms this afternoon and evening. A more active pattern emerges today as a weak shortwave trough moves across far northwest Colorado. Isolated to scattered showers and thunderstorms are likely during the afternoon and evening, with a modest severe weather threat. High temperatures will be around 90°F with dewpoints in the upper 40s and precipitable water (PWAT) values around 0.75”. Storm motions will be from west to east around 15-20 mph broadly across the District. STORM RAINFALL POTENTIAL AND DURATION: Showers and thunderstorms today have the potential to produce between a trace to 0.50” in 10-30 minutes. WORST CASE SCENARIO: A strong thunderstorm may be capable of producing 0.75” or more in 30 minutes or less. A LOOK AHEAD: Thursday will be similar to Wednesday, with scattered showers and thunderstorms expected throughout the day. Early convection may limit afternoon temperatures to the upper 80s across the plains. Better atmospheric moisture will support slightly higher rainfall amounts. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Arapahoe 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Boulder 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Broomfield 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Denver 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Douglas 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Jefferson 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Foothills above 6500ft       Boulder 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Douglas 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW Jefferson 100 PM TO 1000 PM Trace (70%) to 0.25" (40%) to 0.5" (10%) LOW MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]