Flash Flood Prediction Program

Time: 810 PM Mon July 5, 2021 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S WILL BE ALLOWED TO EXPIRE AT 9:00 PM - Message 1's will be allowed to expire at 9:00pm as the threat for heavy rainfall has come to an end. - Temperatures have cooled behind a round of strong thunderstorms for south and eastern portions of the District that has slowly moved eastward and out of the District at this time. An additional round of rain showers with a few rumbles of thunder will be possible later this evening, but heavy rainfall is not expected. Best chance for an additional round of showers will be between 10pm and 2am. - Overnight lows will drop into the upper 50's to low 60's on the plains with low to mid 50's along the foothills. Tomorrow will be similar with another chance for strong to severe thunderstorms in the afternoon and early evening with another likely threat for heavy rainfall. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers will produce a trace to 0.2" of rainfall in 10-30 minutes. A weak to moderate thunderstorm will produce 0.2-0.5" in 10-30 minutes. WORST CASE SCENARIO: A moderate to strong thunderstorm has the potential to produce 0.5-1.0" in 60-90 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 900 PM Current TO 900 PM Jefferson County 1 Current TO 900 PM Current TO 900 PM Broomfield County 1 Current TO 900 PM Current TO 900 PM Douglas County 1 Current TO 900 PM Current TO 900 PM Adams County 1 Current TO 900 PM Current TO 900 PM Denver County 1 Current TO 900 PM Current TO 900 PM DIA 1 Current TO 900 PM Current TO 900 PM Arapahoe County 1 Current TO 900 PM Current TO 900 PM the City of Aurora 1 Current TO 900 PM Current TO 900 PM Arvada 1 Current TO 900 PM Current TO 900 PM Wheat Ridge 1 Current TO 900 PM Current TO 900 PM Lakewood 1 Current TO 900 PM Current TO 900 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Arapahoe Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Boulder Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Broomfield Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Denver Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Douglas Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Jefferson Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Foothills above 6500ft       Boulder Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Douglas Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) ISSUED Jefferson Current TO 200 AM TUE Trace (30%) to 0.2" (15%) to 0.5" (5%) 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]