Time: 944 PM Sat June 5, 2021 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S ISSUED FOR DOUGLAS COUNTY WILL BE ALLOWED TO EXPIRE AT 10:00 PM - Message 1's will be allowed to expire for Douglas County since the threat for Heavy Rain has come to and end. - Late this afternoon a gust front pushed into Douglas County from the south resulting in explosive storm development which included heavy rain, lots of lightning and large hail. Additional storms would fire up along outflow boundaries well into the evening with thunderstorms clinging to the foothills and moving north into Boulder at this time. As these thunderstorms move northward, they are decreasing rapidly into just rain showers and will diminish completely by midnight with skies gradually clearing into Sunday. - Overnight will be fairly mild as lows drop into the 50's. Another chance for rain showers/thunderstorms tomorrow, with a chance for heavy rainfall once again as warm temperatures, decent surface moisture with dew points in the 40's with relatively slow storm motions. At this time, the best chance for storm initiation will be around midday tomorrow with chances continuing into the evening. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers and weak thunderstorms will produce a TR-0.1" (Favoring NW portions of the District). A moderate thunderstorm could produce 0.1-0.3" in 10-30 minutes. WORST CASE SCENARIO: A slower moving thunderstorm has the potential to produce 0.3-0.8" in 60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 1000 PM Current TO 1000 PM Jefferson County 1 Current TO 1000 PM Current TO 1000 PM Broomfield County 1 Current TO 1000 PM Current TO 1000 PM Douglas County 1 Current TO 1000 PM Current TO 1000 PM Adams County 1 Current TO 1000 PM Current TO 1000 PM Denver County 1 Current TO 1000 PM Current TO 1000 PM DIA 1 Current TO 1000 PM Current TO 1000 PM Arapahoe County 1 Current TO 1000 PM Current TO 1000 PM the City of Aurora 1 Current TO 1000 PM Current TO 1000 PM Arvada 1 Current TO 1000 PM Current TO 1000 PM Wheat Ridge 1 Current TO 1000 PM Current TO 1000 PM Lakewood 1 Current TO 1000 PM Current TO 1000 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1159 PM SAT Trace (30%) to 0.1" (10%) to 0.3" (5%) NONE Arapahoe Current TO 1159 PM SAT Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE Boulder Current TO 1159 PM SAT Trace (60%) to 0.1" (30%) to 0.3" (10%) NONE Broomfield Current TO 1159 PM SAT Trace (30%) to 0.1" (10%) to 0.3" (5%) NONE Denver Current TO 1159 PM SAT Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE Douglas Current TO 1159 PM SAT Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE Jefferson Current TO 1159 PM SAT Trace (30%) to 0.1" (10%) to 0.3" (5%) NONE Foothills above 6500ft       Boulder Current TO 1159 PM SAT Trace (50%) to 0.1" (20%) to 0.3" (10%) NONE Douglas Current TO 1159 PM SAT Trace (30%) to 0.1" (10%) to 0.3" (5%) NONE Jefferson Current TO 1159 PM SAT Trace (30%) to 0.1" (10%) to 0.3" (5%) 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]