Time: 349 AM Thu July 28, 2022 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE'S WILL BE ALLOWED TO EXPIRE AT 4:00 AM - Message 1's will be allowed to expire for all Counties at 4:00 AM as the threat for heavy rainfall has lowered for the remainder of the overnight period. Thunderstorms to the N of the District diminished upon approach leaving some lighter rain showers in their wake. - Strong thunderstorms developed over the District hours ago producing heavy rainfall and hail resulting in excessive runoff roadways and isolated areas of flash flooding. The thunderstorm activity has long since diminished. - There will be a few light rain showers and possibly a weak thunderstorm that into early Thursday morning but heavy rainfall is no longer anticipated. Another active thunderstorm day is expected later today and with all of the rain yesterday it may not take as much rain this afternoon to produce excessive runoff as the ground has become saturated in some areas. STORM RAINFALL POTENTIAL AND DURATION: Additional rain showers and possibly a weak thunderstorm overnight will produce a trace to 0.3" of rain in 10-30 minutes. WORST CASE SCENARIO: A moderate thunderstorm is able to develop in a cooling airmass with the potential to produce 0.3-0.8" of rain in 10-30 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 400 AM Current TO 400 AM Arvada 1 Current TO 400 AM Current TO 400 AM the City of Aurora 1 Current TO 400 AM Current TO 400 AM Arapahoe County 1 Current TO 400 AM Current TO 400 AM DIA 1 Current TO 400 AM Current TO 400 AM Denver County 1 Current TO 400 AM Current TO 400 AM Adams County 1 Current TO 400 AM Current TO 400 AM Douglas County 1 Current TO 400 AM Current TO 400 AM Jefferson County 1 Current TO 400 AM Current TO 400 AM Broomfield County 1 Current TO 400 AM Current TO 400 AM Wheat Ridge 1 Current TO 400 AM Current TO 400 AM Lakewood 1 Current TO 400 AM Current TO 400 AM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Arapahoe Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Boulder Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Broomfield Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Denver Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Douglas Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Jefferson Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Foothills above 6500ft       Boulder Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Douglas Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Jefferson Current TO 1000 AM THU Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]