Flash Flood Prediction Program

Time: 1208 AM Sat June 3, 2023 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S CONTINUE VALID UNTIL 2:00 AM SATURDAY Message 1’s will continue valid until 2:00 AM Saturday as moderate to brief heavy rain still lingers over southern areas of the District. A boundary pushed back to the west into the District and produced thunderstorms with moderate heavy rainfall over the past few hours. These thunderstorms have peaked in intensity and are now weak to moderate for areas S of I-70. The weakening trend and southern progression of the rain is expected to continue over the next 1-2 hours and Messages will likely be allowed to expire. Additional rain showers will likely re-develop after 2:00 AM and persist into daybreak Saturday but are expected to be light in intensity. STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak thunderstorms will produce 0.1-0.3" in 10-30 minutes. A moderate to strong thunderstorm may result in rainfall rates of 0.3-0.8" in 10-30 minutes. WORST CASE SCENARIO: A moderate to strong stationary thunderstorm may result in up to 1.6” in 45-75 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 200 AM Current TO 100 AM Jefferson County 1 Current TO 200 AM Current TO 100 AM Broomfield County 1 Current TO 200 AM Current TO 100 AM Douglas County 1 Current TO 200 AM Current TO 100 AM Adams County 1 Current TO 200 AM Current TO 100 AM Denver County 1 Current TO 200 AM Current TO 100 AM DIA 1 Current TO 200 AM Current TO 100 AM Arapahoe County 1 Current TO 200 AM Current TO 100 AM the City of Aurora 1 Current TO 200 AM Current TO 100 AM Arvada 1 Current TO 200 AM Current TO 100 AM Wheat Ridge 1 Current TO 200 AM Current TO 100 AM Lakewood 1 Current TO 200 AM Current TO 100 AM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 200 AM SAT 0.1" (40%) to 0.3" (20%) to 0.8" (10%) ISSUED Arapahoe Current TO 200 AM SAT 0.1" (90%) to 0.3" (50%) to 0.8" (20%) ISSUED Boulder Current TO 200 AM SAT 0.1" (40%) to 0.3" (20%) to 0.8" (10%) ISSUED Broomfield Current TO 200 AM SAT 0.1" (40%) to 0.3" (20%) to 0.8" (10%) ISSUED Denver Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (15%) ISSUED Douglas Current TO 200 AM SAT 0.1" (100%) to 0.3" (60%) to 0.8" (30%) ISSUED Jefferson Current TO 200 AM SAT 0.1" (90%) to 0.3" (50%) to 0.8" (20%) ISSUED Foothills above 6500ft       Boulder Current TO 200 AM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (10%) ISSUED Douglas Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (15%) ISSUED Jefferson Current TO 200 AM SAT 0.1" (60%) to 0.3" (30%) to 0.8" (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]