Flash Flood Prediction Program

Time: 650 PM Fri June 21, 2024 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1’S WILL BE ALLOWED TO EXPIRE AT 8:00 PM Message 1’s will be allowed to expire at 10:00pm as the threat of heavy rain has come to an end. A few strong storms impacted the District earlier this afternoon and have since moved out and onto the eastern plains. Skies have cleared over the District and should remain fairly clear into the evening. Another wave of showers and possibly a thunderstorm or two will be possible later this evening, between 9pm-11pm with skies again overnight and into Saturday. Overnight temperatures will drop to around 60 degrees for most of the District with mid to upper 50s along the foothills. High-pressure starts to build tomorrow bringing sunny skies with high temperatures jumping back to around 90 degrees. STORM RAINFALL POTENTIAL AND DURATION: Typical showers will produce a trace to 0.15” total in 10-30 minutes. A moderate shower/thunderstorm will produce 0.15”-0.30” total in 10-30 minutes. WORST CASE SCENARIO: If a stronger storm is able to develop, it will have the potential to produce up to 0.60” in 30-60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 800 PM Current TO 730 PM Jefferson County 1 Current TO 800 PM Current TO 730 PM Broomfield County 1 Current TO 800 PM Current TO 730 PM Douglas County 1 Current TO 800 PM Current TO 730 PM Adams County 1 Current TO 800 PM Current TO 730 PM Denver County 1 Current TO 800 PM Current TO 730 PM DIA 1 Current TO 800 PM Current TO 730 PM Arapahoe County 1 Current TO 800 PM Current TO 730 PM the City of Aurora 1 Current TO 800 PM Current TO 730 PM Arvada 1 Current TO 800 PM Current TO 730 PM Wheat Ridge 1 Current TO 800 PM Current TO 730 PM Lakewood 1 Current TO 800 PM Current TO 730 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1159 PM FRI Trace (30%) to 0.15" (15%) to 0.3" (5%) NONE Arapahoe Current TO 1159 PM FRI Trace (30%) to 0.15" (15%) to 0.3" (5%) NONE Boulder Current TO 1159 PM FRI Trace (30%) to 0.15" (15%) to 0.3" (5%) NONE Broomfield Current TO 1159 PM FRI Trace (30%) to 0.15" (15%) to 0.3" (5%) NONE Denver Current TO 1159 PM FRI Trace (30%) to 0.15" (15%) to 0.3" (5%) NONE Douglas Current TO 1159 PM FRI Trace (30%) to 0.15" (15%) to 0.3" (5%) NONE Jefferson Current TO 1159 PM FRI Trace (30%) to 0.15" (15%) to 0.3" (5%) NONE Foothills above 6500ft       Boulder Current TO 1159 PM FRI Trace (40%) to 0.15" (20%) to 0.3" (10%) NONE Douglas Current TO 1159 PM FRI Trace (40%) to 0.15" (20%) to 0.3" (10%) NONE Jefferson Current TO 1159 PM FRI Trace (40%) to 0.15" (20%) to 0.3" (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]