Time: 934 AM Sat August 13, 2022 Forecaster: Laura Smith ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- HOT WITH A CHANCE FOR AFTERNOON/EVE RAIN/ISOLATED THUNDERSTORMS - Upper-level monsoonal moisture is starting to move into the region this morning, which will support isolated to scattered thunderstorm activity across the District this afternoon and evening. High temperatures will reach the mid 90's with dew points expected to mix out into the upper 40's to low 50's. - Storms will initiate over the high country during the early afternoon and move northwest onto the plains. A cap at the mid-levels around the Denver metro area today could prevent storm development during the afternoon, with a better chance for storm development in the late afternoon/early evening as daytime heating is at its peak. Upper level flow will also be minimal today, resulting in slow storm motions between 5 to 10 mph which will also increase the chance for moderate to brief heavy rain. - Rain showers/isolated thunderstorm activity is expected to persist into the evening, with scattered rain showers dissipating before midnight. Skies will clear overnight with no precipitation expected through tomorrow morning. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers/isolated thunderstorms will produce a trace to 0.2" of rainfall in 10-30 minutes. A moderate to strong thunderstorm will produce 0.2-0.6" WORST CASE SCENARIO: Slow moving storms that form along outflow boundaries, or training of thunderstorm cells may produce 0.6-1.8" in 45-60 minutes. A LOOK AHEAD: On Sunday, high temperatures reach the low to mid 90s with another round of afternoon to evening showers and thunderstorms. Temperatures begin to cool into the 80s early next week with the arrival of an upper-level disturbance. Afternoon to evening showers and thunderstorms are likely Monday and Tuesday, with increasing low-level moisture resulting in locally moderate to heavy rainfall. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 1000 PM Trace (40%) to 0.2" (20%) to 0.6" (10%) LOW Arapahoe 200 PM TO 1000 PM Trace (40%) to 0.2" (20%) to 0.6" (10%) LOW Boulder 200 PM TO 1000 PM Trace (50%) to 0.2" (30%) to 0.6" (15%) LOW Broomfield 200 PM TO 1000 PM Trace (40%) to 0.2" (20%) to 0.6" (10%) LOW Denver 200 PM TO 1000 PM Trace (40%) to 0.2" (20%) to 0.6" (10%) LOW Douglas 200 PM TO 1000 PM Trace (50%) to 0.2" (30%) to 0.6" (15%) LOW Jefferson 200 PM TO 1000 PM Trace (50%) to 0.2" (30%) to 0.6" (15%) LOW Foothills above 6500ft       Boulder 200 PM TO 1000 PM Trace (60%) to 0.2" (40%) to 0.6" (20%) LOW Douglas 200 PM TO 1000 PM Trace (60%) to 0.2" (40%) to 0.6" (20%) LOW Jefferson 200 PM TO 1000 PM Trace (60%) to 0.2" (40%) to 0.6" (20%) LOW MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]