Time: 253 PM Sun July 24, 2022 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S HAVE TRANSITIONED TO MESSAGE 2'S FOR BOULDER AND DOUGLAS COUNTIES/MESSAGE 1'S IN EFFECT FOR REMAINDER OF DISTRICT - Message 1's have transitioned to Message 2's (NWS Flood/Flash Flood Watch) at 3:00 PM for Boulder and Douglas Counties and will be valid until 10:00 PM. Message 1's remain in effect for the remainder of the District and will also be valid until 10:00 PM. Message 1's and 2's may be extended until midnight if a flooding threat remains. - Thunderstorms are beginning to fill in over the area at this time with a SW to NE oriented line grazing SE portions of the District over Arapahoe and Douglas Counties. Additional storms lurk west. Scattered to numerous thunderstorms are expected through the remainder of the afternoon and into the early evening. Prime time for moderate to strong thunderstorms will until 9:00 PM. - Thunderstorms will be efficient rainfall producers very capable of producing heavy downpours that may lead to excessive runoff and possibly flash flooding. STORM RAINFALL POTENTIAL AND DURATION: Weak thunderstorms will produce 0.3-0.8" in 10-30 minutes. Moderate to strong thunderstorms will have the potential to produce rainfall rates of 0.8-2.0 in 10-30 minutes. WORST CASE SCENARIO: A large thunderstorm complex or a slower moving large thunderstorm may result in rainfall rates of 1.0-2.5" in 10-30 minutes and up to 3.5" in 45-75 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME the City of Aurora 1 Current TO 1000 PM Current TO 900 PM Arapahoe County 1 Current TO 1000 PM Current TO 900 PM DIA 1 Current TO 1000 PM Current TO 900 PM Denver County 1 Current TO 1000 PM Current TO 900 PM Adams County 1 Current TO 1000 PM Current TO 900 PM Douglas County 2 Current TO 1000 PM Current TO 900 PM Broomfield County 1 Current TO 1000 PM Current TO 900 PM Jefferson County 1 Current TO 1000 PM Current TO 900 PM Boulder County 2 Current TO 1000 PM Current TO 900 PM Lakewood 1 Current TO 1000 PM Current TO 900 PM Wheat Ridge 1 Current TO 1000 PM Current TO 900 PM Arvada 1 Current TO 1000 PM Current TO 900 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1000 PM SUN 0.2" (95%) to 0.8" (70%) to 2.0" (20%) ISSUED Arapahoe Current TO 1000 PM SUN 0.2" (100%) to 0.8" (75%) to 2.0" (30%) ISSUED Boulder Current TO 1000 PM SUN 0.2" (95%) to 0.8" (70%) to 2.0" (20%) ISSUED Broomfield Current TO 1000 PM SUN 0.2" (95%) to 0.8" (70%) to 2.0" (25%) ISSUED Denver Current TO 1000 PM SUN 0.2" (95%) to 0.8" (70%) to 2.0" (20%) ISSUED Douglas Current TO 1000 PM SUN 0.2" (100%) to 0.8" (75%) to 2.0" (30%) ISSUED Jefferson Current TO 1000 PM SUN 0.2" (95%) to 0.8" (70%) to 2.0" (20%) ISSUED Foothills above 6500ft       Boulder Current TO 1000 PM SUN 0.2" (100%) to 0.8" (75%) to 2.0" (25%) ISSUED Douglas Current TO 1000 PM SUN 0.2" (100%) to 0.8" (75%) to 2.0" (30%) ISSUED Jefferson Current TO 1000 PM SUN 0.2" (100%) to 0.8" (75%) to 2.0" (25%) 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]