Time: 837 AM Sun August 29, 2021 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- COOLER TODAY WITH A SLIGHT CHANCE FOR RAIN SHOWERS/ISOLATED THUNDERSTORMS THIS AFTERNOON FOR SOUTHERN PORTIONS OF THE DISTRICT - A cold front moved through the region yesterday which has brought increased cloud cover over the District this morning. Temperatures today will be a more seasonable low to mid 80's with partly cloudy skies throughout most of the day. - A very slight chance this afternoon for rain showers/isolated thunderstorms, with storms favoring the Palmer Divide at this time. Best chance for storms will be between 3-8pm with skies clearing after sunset. Although storms are favoring the Palmer Divide today, a few scattered rain showers/isolated thunderstorms cannot be completely ruled out this afternoon and evening favoring southern portion of the District. - Partly cloudy skies will help keep temperatures cooler today as well as limit the potential for stronger storms. However, with upper 40's to around 50 dew points currently and little to no chance they will mix out throughout the day, even weak to moderate storms will have the potential to produce brief moderate to heavy rainfall if storms are able to develop this afternoon and early evening. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers/isolated thunderstorms will produce a trace-0.2" of rainfall in 10-30 minutes. A moderate rain shower/thunderstorm will produce 0.2-0.4" in 10-30 minutes. WORST CASE SCENARIO: A strong, slow moving thunderstorm has the potential to produce 1.2" in 60 minutes. A LOOK AHEAD: High-pressure returns briefly Tuesday and Wednesday bringing hot, hazy and dry conditions once again across the District. A strong disturbance is poised to enter the region late Wednesday bringing a chance for rain showers/isolated thunderstorms Wednesday evening with off and on rain showers possible through the overnight and into Thursday. Both Thursday and Friday will have a chance for rain showers with a slight chance for scattered thunderstorms during the afternoon and early evening. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 300 PM TO 800 PM Trace (15%) to 0.2" (10%) to 0.4" (5%) NONE Arapahoe 300 PM TO 800 PM Trace (25%) to 0.2" (15%) to 0.4" (5%) NONE Boulder 300 PM TO 800 PM Trace (15%) to 0.2" (10%) to 0.4" (5%) NONE Broomfield 300 PM TO 800 PM Trace (15%) to 0.2" (10%) to 0.4" (5%) NONE Denver 300 PM TO 800 PM Trace (25%) to 0.2" (15%) to 0.4" (5%) NONE Douglas 300 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.4" (15%) NONE Jefferson 300 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.4" (15%) NONE Foothills above 6500ft       Boulder 300 PM TO 800 PM Trace (15%) to 0.2" (10%) to 0.4" (5%) NONE Douglas 300 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.4" (15%) NONE Jefferson 300 PM TO 800 PM Trace (40%) to 0.2" (20%) to 0.4" (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]