Flash Flood Prediction Program

Time: 930 PM Fri June 2, 2023 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S HAVE BEEN RE-ISSUED AND WILL BE VALID UNTIL 2:00 AM SATURDAY Message 1’s will be allowed to expire as the threat for heavy rainfall has ended at least temporarily. A boundary has pushed back to the west into the District and thunderstorms are developing at this time over parts of Jefferson County. Elevated surface moisture levels will allow storms to be able to produce heavy rain that may lead to excessive runoff. Storms will most likely be pulse-like and move very little from their initiation point. The slow moving nature of the storms may allow for extended periods of moderate to heavy rainfall. Best chances for thunderstorms will be over the next 3-4 hours then precipitation should favor light non-thunderstorm rain showers into Saturday morning. STORM RAINFALL POTENTIAL AND DURATION: 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 the City of Aurora 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Arapahoe County 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY DIA 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Denver County 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Douglas County 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Adams County 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Broomfield County 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Arvada 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Jefferson County 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Boulder County 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Wheat Ridge 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY Lakewood 1 Current TO 200 AM SATURDAY Current TO 100 AM SATURDAY County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 200 AM SAT 0.1" (90%) to 0.3" (60%) to 0.8" (30%) ISSUED Arapahoe Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (20%) ISSUED Boulder Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (20%) ISSUED Broomfield Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (20%) ISSUED Denver Current TO 200 AM SAT 0.1" (90%) to 0.3" (60%) to 0.8" (30%) ISSUED Douglas Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (20%) ISSUED Jefferson Current TO 200 AM SAT 0.1" (90%) to 0.3" (60%) to 0.8" (30%) ISSUED Foothills above 6500ft       Boulder Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (20%) ISSUED Douglas Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (20%) ISSUED Jefferson Current TO 200 AM SAT 0.1" (80%) to 0.3" (40%) to 0.8" (20%) 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]