Flash Flood Prediction Program

Time: 724 PM Sat August 20, 2022 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S CONTINUE VALID FOR THE ENTIRE DISTRICT/HEAVY RAINFALL THREAT QUICKLY DIMINISHING - Message 1's will continue valid for all areas of the District until 9:30 PM but the threat for heavy rainfall is quickly diminishing. - Isolated to widely scattered light rain showers will continue likely over the next few hours. With temperatures currently in the 60's the threat for thunderstorms is very low as the atmosphere is stabilizing. Mainly isolated light rain showers are expected for the remainder of the evening but should a thunderstorm develop it will have the potential to produce brief heavy rain. - After 9 or 10pm conditions are expected to dry out for the remainder of the evening and overnight period. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers will only produce a trace to 0.2" of rainfall in 10-30 minutes. Weak thunderstorms should they develop will have the potential to produce rainfall rates of 0.2-0.6" in 10-30 minutes. WORST CASE SCENARIO: A strong thunderstorm is able to develop producing rainfall rates of 0.4-1.0" in 10-30 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Wheat Ridge 1 Current TO 930 PM 330 PM TO 830 PM Lakewood 1 Current TO 930 PM 330 PM TO 830 PM the City of Aurora 1 Current TO 930 PM 330 PM TO 830 PM Arvada 1 Current TO 930 PM 330 PM TO 830 PM Arapahoe County 1 Current TO 930 PM 330 PM TO 830 PM DIA 1 Current TO 930 PM 330 PM TO 830 PM Denver County 1 Current TO 930 PM 330 PM TO 830 PM Adams County 1 Current TO 930 PM 330 PM TO 830 PM Douglas County 1 Current TO 930 PM 330 PM TO 830 PM Broomfield County 1 Current TO 930 PM 330 PM TO 830 PM Jefferson County 1 Current TO 930 PM 330 PM TO 830 PM Boulder County 1 Current TO 930 PM 330 PM TO 830 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 930 PM SAT Trace (80%) to 0.2" (30%) to 0.6" (5%) ISSUED Arapahoe Current TO 930 PM SAT Trace (75%) to 0.2" (25%) to 0.6" (5%) ISSUED Boulder Current TO 930 PM SAT Trace (90%) to 0.2" (40%) to 0.6" (10%) ISSUED Broomfield Current TO 930 PM SAT Trace (90%) to 0.2" (40%) to 0.6" (10%) ISSUED Denver Current TO 930 PM SAT Trace (75%) to 0.2" (25%) to 0.6" (5%) ISSUED Douglas Current TO 930 PM SAT Trace (80%) to 0.2" (30%) to 0.6" (5%) ISSUED Jefferson Current TO 930 PM SAT Trace (80%) to 0.2" (30%) to 0.6" (5%) ISSUED Foothills above 6500ft       Boulder Current TO 930 PM SAT Trace (90%) to 0.2" (40%) to 0.6" (10%) ISSUED Douglas Current TO 930 PM SAT Trace (90%) to 0.2" (40%) to 0.6" (10%) ISSUED Jefferson Current TO 930 PM SAT Trace (90%) to 0.2" (40%) to 0.6" (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]