Flash Flood Prediction Program

Time: 1026 PM Sat August 14, 2021 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S WILL BE ALLOWED TO EXPIRE FOR PORTIONS OF THE DISTRICT AT 11:00 PM - Message 1's will be allowed to expire for Jefferson County, incl. Wheat Ridge, Lakewood, Arvada, Denver County, Arapahoe County, incl. Aurora & Douglas County at 11:00pm as the threat for heavy rainfall has come to an end. - A disturbance from the NW moved through the District earlier this evening resulting in rapid storm development for areas south of I-70. At this time, a few lingering rain showers towards the eastern portion of the District will continue to move S/SE as they continue to weaken. - Skies will gradually clear through the overnight leading to mild conditions with lows dropping into the upper 50's to low 60's for the plains with low to mid 50's along the foothills. STORM RAINFALL POTENTIAL AND DURATION: weak rain showers will produce a trace to 0.1" in 10-30 minutes. A moderate rain shower could produce 0.1-0.3" in 10-30 minutes. WORST CASE SCENARIO: A thunderstorm or slow moving rain showers has the potential to produce 0.3-0.8" in under 60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 1100 PM Current TO 1030 PM Jefferson County 1 Current TO 1100 PM Current TO 1030 PM Broomfield County 1 Current TO 1100 PM Current TO 1030 PM Douglas County 1 Current TO 1100 PM Current TO 1030 PM Adams County 1 Current TO 1100 PM Current TO 1030 PM Denver County 1 Current TO 1100 PM Current TO 1030 PM DIA 1 Current TO 1100 PM Current TO 1030 PM Arapahoe County 1 Current TO 1100 PM Current TO 1030 PM the City of Aurora 1 Current TO 1100 PM Current TO 1030 PM Arvada 1 Current TO 1100 PM Current TO 1030 PM Wheat Ridge 1 Current TO 1100 PM Current TO 1030 PM Lakewood 1 Current TO 1100 PM Current TO 1030 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" (15%) to 0.3" (10%) NONE Arapahoe Current TO 1159 PM SAT Trace (30%) to 0.1" (15%) to 0.3" (10%) NONE Boulder Current TO 1159 PM SAT Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE Broomfield Current TO 1159 PM SAT Trace (20%) 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 (30%) to 0.1" (15%) to 0.3" (10%) NONE Jefferson Current TO 1159 PM SAT Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE Foothills above 6500ft       Boulder 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 (20%) 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]