Flash Flood Prediction Program

Time: 1140 PM Sun August 27, 2023 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1’S WILL BE ALLOWED TO EXPRIED FOR ARAPAHOE AND DOUGLAS COUNTIES AT 11:59 PM Message 1’s will be allowed to expire at 11:59pm for Arapahoe and Douglas Counties as the threat of heavy rainfall has come to an end. After a strong round of showers/thunderstorms a few lingering showers continue for eastern portions of the District and will slowly taper off over the next couple of hours. Skies will gradually clear through the overnight with a few areas of patchy fog possible through daybreak tomorrow. Another good chance for storms tomorrow afternoon and into tomorrow evening with at least a moderate chance for heavy rainfall producing storms. STORM RAINFALL POTENTIAL AND DURATION: Typical showers will produce rainfall of a trace to 0.20” total in 10-30 minutes. WORST CASE SCENARIO: A moderate to strong shower will have the potential to produce rainfall of 0.20" to 0.40” total in 10-30 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Arapahoe County 1 Current TO 1159 PM Current TO 1159 PM Douglas County 1 Current TO 1159 PM Current TO 1159 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 200 AM MON Trace (20%) to 0.2" (10%) to 0.4" (5%) NONE Arapahoe Current TO 200 AM MON Trace (60%) to 0.2" (30%) to 0.4" (15%) NONE Boulder Current TO 200 AM MON Trace (20%) to 0.2" (10%) to 0.4" (5%) NONE Broomfield Current TO 200 AM MON Trace (20%) to 0.2" (10%) to 0.4" (5%) NONE Denver Current TO 200 AM MON Trace (40%) to 0.2" (20%) to 0.4" (10%) NONE Douglas Current TO 200 AM MON Trace (75%) to 0.2" (50%) to 0.4" (25%) NONE Jefferson Current TO 200 AM MON Trace (20%) to 0.2" (10%) to 0.4" (5%) NONE Foothills above 6500ft       Boulder Current TO 200 AM MON Trace (20%) to 0.2" (10%) to 0.4" (5%) NONE Douglas Current TO 200 AM MON Trace (60%) to 0.2" (30%) to 0.4" (10%) NONE Jefferson Current TO 200 AM MON Trace (20%) to 0.2" (10%) to 0.4" (5%) 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]