Flash Flood Prediction Program

Time: 946 PM Thu June 15, 2023 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1’S HAVE BEEN EXTENDED UNTIL 11:59 PM Message 1’s have been extended to 11:59pm as the threat of heavy rainfall remains over the District. A gust front from the north stirred the pot at this late hour. These storms will likely pulse up and down over the District over the next couple of hours as they move west to east. Low to mid 50’s dew points, combined with an approaching trough of low-pressure, has resulted in good dynamics for late evening rain and thunderstorms. A few pockets of rain will likely be heavy at times, with a chance of a quick 0.5” in 10 minutes likely being the largest threat. However, due to an already saturated surface even general showers will result in pooling of water and rising creeks/streams. The best chance for storms will be from now through midnight with a few lingering off and on showers possible through daybreak tomorrow. STORM RAINFALL POTENTIAL AND DURATION: Typical showers will produce a trace to 0.25” total, in 10-30 minutes. A weak to moderate thunderstorm will produce 0.25-0.75” total in 10-30 minutes. WORST CASE SCENARIO: A stronger thunderstorm, or training of moderate showers/thunderstorms will have the potential to produce 1.5” total in 45-60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 1159 PM Current TO 1130 PM Jefferson County 1 Current TO 1159 PM Current TO 1130 PM Broomfield County 1 Current TO 1159 PM Current TO 1130 PM Douglas County 1 Current TO 1159 PM Current TO 1130 PM Adams County 1 Current TO 1159 PM Current TO 1130 PM Denver County 1 Current TO 1159 PM Current TO 1130 PM DIA 1 Current TO 1159 PM Current TO 1130 PM Arapahoe County 1 Current TO 1159 PM Current TO 1130 PM the City of Aurora 1 Current TO 1159 PM Current TO 1130 PM Arvada 1 Current TO 1159 PM Current TO 1130 PM Wheat Ridge 1 Current TO 1159 PM Current TO 1130 PM Lakewood 1 Current TO 1159 PM Current TO 1130 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Arapahoe Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Boulder Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Broomfield Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Denver Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Douglas Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Jefferson Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Foothills above 6500ft       Boulder Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Douglas Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (20%) ISSUED Jefferson Current TO 1159 PM THU Trace (95%) to 0.25" (50%) to 0.75" (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]