Time: 909 AM Sun May 23, 2021 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- WARM AND WINDY WITH A CHANCE FOR AFTERNOON THUNDERSTORMS FAVORING EASTERN PORTIONS OF THE DISTRICT - Warm and windy today as high temperatures reach the mid to upper 70's on the plains with mid to upper 60's along the foothills. Isolated areas of patchy fog this morning as dew points remain in the low 50's from overnight rain showers. Conditions today will dry out rapidly at the surface as strong W/SW winds with gust up to 40mph will push all the surface moisture eastward where a good chance for severe weather will occur once again for Colorado's Eastern Plains. - Cannot completely rule out an isolated rain shower/thunderstorm this afternoon over the District, however, the heavy rainfall threat will remain minimal as storm motions will be fairly brisk between 20-30mph from W/SW to E/NE helping limit point rainfall amounts. Largest threat for storms today will be gusty winds, lightning and hail up to 1". Best chance for storm development today will be from 2-6pm with skies clearing through the evening and into the overnight. - Overnight lows will decrease into the upper 40's to low 50's on the plains with low to mid 40's along the foothills with mild conditions. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers/isolated thunderstorms will have the potential to produce a TR-0.1" in 10-30 minutes. A moderate thunderstorm will have the potential to produce 0.1-0.3" in 10-30 minutes. WORST CASE SCENARIO: An anchored thunderstorms or training of thunderstorms could produce 0.3-0.6" of rainfall in 30-60 minutes. A LOOK AHEAD: High pressure starts to build over the region tomorrow leading to dry conditions starting the week with temperatures in the upper 70's to low 80's through Wednesday. A slight chance Wednesday afternoon for widely scattered high-based thunderstorms with no heavy rainfall threat at this time. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 600 PM Trace (40%) to 0.1" (15%) to 0.3" (5%) NONE Arapahoe 200 PM TO 600 PM Trace (40%) to 0.1" (15%) to 0.3" (5%) NONE Boulder 200 PM TO 600 PM Trace (25%) to 0.1" (10%) to 0.3" (5%) NONE Broomfield 200 PM TO 600 PM Trace (25%) to 0.1" (10%) to 0.3" (5%) NONE Denver 200 PM TO 600 PM Trace (30%) to 0.1" (15%) to 0.3" (5%) NONE Douglas 200 PM TO 600 PM Trace (40%) to 0.1" (15%) to 0.3" (5%) NONE Jefferson 200 PM TO 600 PM Trace (25%) to 0.1" (10%) to 0.3" (5%) NONE Foothills above 6500ft       Boulder 200 PM TO 600 PM Trace (25%) to 0.1" (10%) to 0.3" (5%) NONE Douglas 200 PM TO 600 PM Trace (25%) to 0.1" (10%) to 0.3" (5%) NONE Jefferson 200 PM TO 600 PM Trace (25%) to 0.1" (10%) to 0.3" (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]