Time: 856 AM Tue June 1, 2021 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- WARM TODAY WITH A CHANCE FOR AFTERNOON/EARLY EVENING RAIN SHOWERS/ISOLATED THUNDERSTORMS - NW flow aloft will dominate over the region today as temperatures remain slightly below average with highs in the upper 60's to low 70's this afternoon. - A weak disturbance moves in from the NW this afternoon, which will bring increased cloud cover along with a chance for scattered rain showers/isolated thunderstorms. Storm motions will be between 10-20mph, which will limit point rainfall amounts. Typical rain showers/isolated thunderstorms will produce a trace to 0.1" of rain in 10-30 minutes, however a slower moving thunderstorm, or training of thunderstorms, especially along the foothills, could bring isolated higher amounts. Best chance for rain showers/isolated thunderstorms will be from 1-7pm, with skies clearing into the evening. - Overnight lows will drop into the upper 40's to low 50's on the plains with low to mid 40's along the foothills. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers and weak thunderstorms will produce a trace to 0.1" of rain. A moderate thunderstorm over the higher terrain may result in 0.1-0.3" in 10-30 minutes. WORST CASE SCENARIO: A slower moving moderate thunderstorm, or training of thunderstorms has the potential to produce 0.6-1.0" in 30-60 minutes. A LOOK AHEAD: High-pressure start to build this evening and into tomorrow bringing mild and dry conditions through the rest of the week. Temperatures will also begin to increase tomorrow with highs returning to average in the mid 70's to mid 80's through Friday. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 700 PM Trace (50%) to 0.1" (30%) to 0.3" (10%) NONE Arapahoe 200 PM TO 700 PM Trace (50%) to 0.1" (30%) to 0.3" (10%) NONE Boulder 200 PM TO 700 PM Trace (50%) to 0.1" (30%) to 0.3" (10%) NONE Broomfield 200 PM TO 700 PM Trace (50%) to 0.1" (30%) to 0.3" (10%) NONE Denver 200 PM TO 700 PM Trace (50%) to 0.1" (30%) to 0.3" (10%) NONE Douglas 200 PM TO 700 PM Trace (50%) to 0.1" (30%) to 0.3" (10%) NONE Jefferson 200 PM TO 700 PM Trace (50%) to 0.1" (30%) to 0.3" (10%) NONE Foothills above 6500ft       Boulder 100 PM TO 600 PM Trace (75%) to 0.1" (50%) to 0.3" (20%) NONE Douglas 100 PM TO 700 PM Trace (75%) to 0.1" (50%) to 0.3" (20%) NONE Jefferson 100 PM TO 700 PM Trace (75%) to 0.1" (50%) to 0.3" (20%) 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]