Flash Flood Prediction Program

Time: 718 PM Thu July 6, 2023 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1’s CONTINUE TO BE VALID AS THE THREAT OF HEAVY RAIN REMAINS Message 1’s will continue to be valid as the threat of heavy rain remains until 10:00pm. A few strong thunderstorms impacted eastern portions of the District earlier this afternoon and evening and have since moved eastward and onto the plains. A slight chance remains for additional storm development through 10pm, as upper-level support will hold over the area over the next couple of days. However, cooler temperatures and losing daytime heating will result in a lower chance for additional thunderstorms. Another chance for late evening showers, and off and on overnight showers into daybreak Friday. Quick storm motions, between 20-30mph will limit point rainfall amounts. Similar conditions remain in place Friday with another good chance for afternoon thunderstorms, with a slight chance for severe storms with large hail, winds 60+mph and even an isolated land spout/weak tornado or two. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers will produce TR-0.25” total in 10-30 minutes. A weak to moderate thunderstorm will produce 0.25-0.75” total in 10-30 minutes. WORST CASE SCENARIO: A strong thunderstorm, or training of moderate thunderstorm cells has the potential to produce 1.50” in up to 60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME the City of Aurora 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 Denver County 1 Current TO 1000 PM Current TO 900 PM Adams 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 Arvada 1 Current TO 1000 PM Current TO 900 PM Wheat Ridge 1 Current TO 1000 PM Current TO 900 PM Lakewood 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 THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Arapahoe Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Boulder Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Broomfield Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Denver Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Douglas Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Jefferson Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Foothills above 6500ft       Boulder Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Douglas Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (10%) ISSUED Jefferson Current TO 1000 PM THU Trace (50%) to 0.25" (25%) to 0.75" (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]