Flash Flood Prediction Program

Time: 720 PM Wed July 20, 2022 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S WILL BE ALLOWED TO EXPIRE AT 8PM - Message 1's will be allowed to expire at 8:00pm as the threat for heavy rainfall has ended for the day. - An outflow boundary from storms that originated to the S of the Palmer Divide early in the afternoon moved northward and intensified thunderstorms over the District producing areas of moderate and brief heavy rainfall. The thunderstorm activity has diminished over the past hour and a more stable air mass is currently in place and thunderstorms are no longer expected. - Isolated light rain showers will continue possible into the evening hours with dry conditions expected well ahead of midnight. Best chances for additional shower activity will be in and near the foothills. STORM RAINFALL POTENTIAL AND DURATION: Isolated rain showers and possibly a weak thunderstorm will produce a trace to 0.2" of rain. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 800 PM 500 PM TO 700 PM Jefferson County 1 Current TO 800 PM 500 PM TO 700 PM Broomfield County 1 Current TO 800 PM 500 PM TO 700 PM Douglas County 1 Current TO 800 PM 500 PM TO 700 PM Adams County 1 Current TO 800 PM 500 PM TO 700 PM Denver County 1 Current TO 800 PM 500 PM TO 700 PM DIA 1 Current TO 800 PM 500 PM TO 700 PM Arapahoe County 1 Current TO 800 PM 500 PM TO 700 PM the City of Aurora 1 Current TO 800 PM 500 PM TO 700 PM Arvada 1 Current TO 800 PM 500 PM TO 700 PM Wheat Ridge 1 Current TO 800 PM 500 PM TO 700 PM Lakewood 1 Current TO 800 PM 500 PM TO 700 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1000 PM WED Trace (20%) to 0.1" (10%) to 0.2" (5%) NONE Arapahoe Current TO 1000 PM WED Trace (30%) to 0.1" (15%) to 0.2" (5%) NONE Boulder Current TO 1000 PM WED Trace (30%) to 0.1" (15%) to 0.2" (5%) NONE Broomfield Current TO 1000 PM WED Trace (30%) to 0.1" (15%) to 0.2" (5%) NONE Denver Current TO 1000 PM WED Trace (20%) to 0.1" (10%) to 0.2" (5%) NONE Douglas Current TO 1000 PM WED Trace (30%) to 0.1" (15%) to 0.2" (5%) NONE Jefferson Current TO 1000 PM WED Trace (30%) to 0.1" (15%) to 0.2" (5%) NONE Foothills above 6500ft       Boulder Current TO 1000 PM WED Trace (50%) to 0.1" (25%) to 0.2" (10%) NONE Douglas Current TO 1000 PM WED Trace (50%) to 0.1" (25%) to 0.2" (10%) NONE Jefferson Current TO 1000 PM WED Trace (50%) to 0.1" (25%) to 0.2" (10%) 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]