Flash Flood Prediction Program

Time: 859 AM Sun June 5, 2022 Forecaster: Brad Simmons ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- ISOLATED TO WIDELY SCATTERED AFTERNOON AND EVENING THUNDERSTORMS - Mid and upper level moisture pushing through the state will produce partly to mostly cloudy skies through the day today. Even with the increased cloud cover today temperatures will warm into the low and mid 80's over the plains with 70's in the Front Range foothills. Normal high for Denver today is 80 degrees. - The additional upper level moisture will result in a little better thunderstorm coverage this afternoon over the District compared to yesterday but not everyone will experience a storm today. The typical storms that develop this afternoon will be high-based producing light rainfall and gusty winds. Gusts may reach or exceed 30mph near active storms. If a moderate thunderstorm is able to develop a brief wetting rain is possible but heavy rainfall is not anticipated. - Thunderstorms will initiate over the foothills between noon and 2pm with prime time for storms over the plains from 2-8pm. Upper level steering winds from the W to NW at 15-20mph will keep storms moving along and any meaningful rainfall brief. After 8pm conditions will be drying out with possibly an isolated rain shower overnight favoring the higher mountains and foothills W of the District. STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak thunderstorms will produce a trace to 0.1" of rain. A moderate thunderstorm will have the potential to produce 0.1-0.3" rainfall rates in 10-30 minutes. WORST CASE SCENARIO: Higher moisture values work their way into the I-25 corridor this afternoon allowing for a strong thunderstorm to develop with the potential to produce rainfall rates of 0.2-0.6" in 10-30 minutes. A LOOK AHEAD: An upper level disturbance will move through the area on Monday along with a weak surface cold front. The result will be slightly cooler temperatures in the upper 70's to lower 80's for highs over the plains with an increase in shower and thunderstorm activity in the afternoon and evening. Additional surface moisture behind the front will help to fuel storms and moderate to strong thunderstorms may develop with the potential to produce small areas of moderate to brief heavy rainfall. Additional light rain showers continue possible overnight Monday with dry conditions ahead of daybreak Tuesday morning. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 800 PM Trace (80%) to 0.1" (50%) to 0.3" (15%) NONE Arapahoe 200 PM TO 800 PM Trace (80%) to 0.1" (50%) to 0.3" (15%) NONE Denver 200 PM TO 800 PM Trace (80%) to 0.1" (50%) to 0.3" (15%) NONE Boulder 100 PM TO 800 PM Trace (80%) to 0.1" (50%) to 0.3" (15%) NONE Broomfield 100 PM TO 800 PM Trace (80%) to 0.1" (50%) to 0.3" (15%) NONE Douglas 100 PM TO 800 PM Trace (80%) to 0.1" (50%) to 0.3" (15%) NONE Jefferson 100 PM TO 800 PM Trace (80%) to 0.1" (50%) to 0.3" (15%) NONE Foothills above 6500ft       Boulder 1200 PM TO 800 PM Trace (90%) to 0.1" (60%) to 0.3" (20%) NONE Douglas 1200 PM TO 800 PM Trace (90%) to 0.1" (60%) to 0.3" (20%) NONE Jefferson 1200 PM TO 800 PM Trace (90%) to 0.1" (60%) 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]