Flash Flood Prediction Program

Time: 903 AM Mon September 19, 2022 Forecaster: Brad Simmons ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- UNSEASONABLY WARM AND GENERALLY DRY - Temperatures will continue to run above seasonal averages with afternoon highs topping out in the upper 80's to around 90 over the plains and 70's in the Front Range foothills. Normal high for Denver today is 79 degrees, record high is 96 degrees. - High pressure will dominate the weather today leading to dry conditions most areas and a slight chance for an isolated rain shower or weak thunderstorm over the foothills and S/SE areas of the District. Moisture is lacking at the surface and the most likely outcome is a build up of clouds making for partly to mostly cloudy skies late in the afternoon and maybe a few sprinkles along with gusty winds. - If a rain shower or weak thunderstorm is observed it will be between 4-10pm. After 10pm dry conditions are expected for the remainder of the evening and overnight period. STORM RAINFALL POTENTIAL AND DURATION: Isolated rain showers weak thunderstorms will produce a trace to 0.1" of rain. A LOOK AHEAD: Another warm day on Tuesday with highs in the upper 80's to around 90 over the plains ahead of a cold front that will move through overnight. There will be a slight chance for a few rain showers or isolated thunderstorms ahead of the front Tuesday afternoon and evening with rain showers starting to fill in overnight into Wednesday morning. Wednesday will be much cooler and rainy with highs in the 50's to lower 60's. Rain showers will become widespread as the day progresses with 0.50-1.25" of moisture expected at this time from Wednesday morning into Thursday morning. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 400 PM TO 1000 PM Trace (15%) to 0.1" (5%) NONE Arapahoe 400 PM TO 1000 PM Trace (20%) to 0.1" (10%) NONE Boulder 400 PM TO 1000 PM Trace (15%) to 0.1" (5%) NONE Broomfield 400 PM TO 1000 PM Trace (15%) to 0.1" (5%) NONE Denver 400 PM TO 1000 PM Trace (15%) to 0.1" (5%) NONE Douglas 400 PM TO 1000 PM Trace (20%) to 0.1" (10%) NONE Jefferson 400 PM TO 1000 PM Trace (15%) to 0.1" (5%) NONE Foothills above 6500ft       Boulder 300 PM TO 1000 PM Trace (20%) to 0.1" (10%) NONE Douglas 300 PM TO 1000 PM Trace (30%) to 0.1" (10%) NONE Jefferson 300 PM TO 1000 PM Trace (30%) to 0.1" (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]