Flash Flood Prediction Program

Time: 255 AM Fri June 30, 2023 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1’S WILL BE ALLOWED TO EXPIRE AT 4AM Message 1’s will be allowed to expire at 4am as the threat for heavy rainfall has come to an end. A few linger showers/isolated thunderstorms are impacting eastern portions of the District at this time, but should be out of the District by 4am. Minimal to no additional shower activity is expected through daybreak, however with elevated surface moisture in place, a LOW chance for Messages to be issued through daybreak. Another good chance for storms this afternoon. The best chance currently will be between noon and 5pm with skies likely clearing into the evening. Once again some of these storms could become severe, bringing large hail, gusty winds, and possibly an isolated tornado, favoring areas east of I-25. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers will produce a trace to 0.20” total in 10-30 minutes. A weak to moderate thunderstorm could produce 0.20-0.50” total in 10-30 minutes. WORST CASE SCENARIO: A stronger cell is able to develop and will have the potential to produce up to 1” in 45-60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Lakewood 1 Current TO 400 AM Current TO 330 AM Wheat Ridge 1 Current TO 400 AM Current TO 330 AM Arvada 1 Current TO 400 AM Current TO 330 AM the City of Aurora 1 Current TO 400 AM Current TO 330 AM Arapahoe County 1 Current TO 400 AM Current TO 330 AM DIA 1 Current TO 400 AM Current TO 330 AM Denver County 1 Current TO 400 AM Current TO 330 AM Adams County 1 Current TO 400 AM Current TO 330 AM Douglas County 1 Current TO 400 AM Current TO 330 AM Broomfield County 1 Current TO 400 AM Current TO 330 AM Jefferson County 1 Current TO 400 AM Current TO 330 AM Boulder County 1 Current TO 400 AM Current TO 330 AM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Arapahoe Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Boulder Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Broomfield Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Denver Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Douglas Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Jefferson Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Foothills above 6500ft       Boulder Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Douglas Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW Jefferson Current TO 700 AM FRI Trace (20%) to 0.2" (10%) to 0.5" (10%) LOW MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]