Time: 952 AM Tue May 28, 2024 Forecaster: Laura Smith ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- Afternoon to evening showers and thunderstorms This week will be more active as northwesterly upper-level winds transport Pacific atmospheric moisture into the region. This morning will be mostly sunny followed by isolated afternoon to evening showers and thunderstorms. Afternoon highs will reach the upper 70s to low 80s, dew points in the upper 30s to low 40s, and precipitable water (PWAT) values around 0.5”-0.6”. Chances for isolated showers and thunderstorms will gradually improve throughout the day, becoming scattered by the late afternoon. Storm motions will be from west to east around 15-20 mph. Storms will begin clearing after sunset, with precipitation concluding by the mid to late evening. STORM RAINFALL POTENTIAL AND DURATION: Typical showers will produce a trace to 0.10” total in 15-30 minutes. A moderate shower/thunderstorm will produce up to 0.20” in 15-30 minutes. WORST CASE SCENARIO: There is a slight chance stronger storms east of the District produce easterly outflows that elevate surface dewpoints, improving chances for moderate to briefly heavy rainfall. This scenario, coupled with slower storm motions, support thunderstorms capable of producing up to 0.50” of rainfall in up to 30 minutes. A LOOK AHEAD: On Wednesday, mostly sunny morning skies will allow afternoon highs to climb into the 80s once again. Chances for isolated to scattered showers and thunderstorms improve during the afternoon and evening. On Thursday, another round of scattered afternoon to evening showers and thunderstorms is possible ahead of a weak cold front overnight. Friday will be active following the frontal passage, with temperatures in the upper 70s to low 80s and chances for isolated to scattered afternoon and evening thunderstorms. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 1000 PM Trace (35%) to 0.1" (25%) to 0.2" (15%) NONE Arapahoe 200 PM TO 1000 PM Trace (35%) to 0.1" (25%) to 0.2" (15%) NONE Boulder 200 PM TO 1000 PM Trace (35%) to 0.1" (25%) to 0.2" (15%) NONE Broomfield 200 PM TO 1000 PM Trace (35%) to 0.1" (25%) to 0.2" (15%) NONE Denver 200 PM TO 1000 PM Trace (35%) to 0.1" (25%) to 0.2" (15%) NONE Douglas 200 PM TO 1000 PM Trace (35%) to 0.1" (25%) to 0.2" (15%) NONE Jefferson 200 PM TO 1000 PM Trace (35%) to 0.1" (25%) to 0.2" (15%) NONE Foothills above 6500ft       Boulder 100 PM TO 1000 PM Trace (45%) to 0.1" (35%) to 0.2" (25%) NONE Douglas 100 PM TO 1000 PM Trace (45%) to 0.1" (35%) to 0.2" (25%) NONE Jefferson 100 PM TO 1000 PM Trace (45%) to 0.1" (35%) to 0.2" (25%) 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]