Flash Flood Prediction Program

Time: 842 AM Wed July 27, 2022 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- WARMER TODAY WITH A GOOD CHANCE FOR LATE EVENING/OVERNIGHT RAIN/THUNDERSTORMS - Northwesterly flow aloft will dominate over the region today, bringing clear skies this morning with high temperatures in the mid 80's to around 90 degrees this afternoon. A slight chance for widely scattered afternoon rain showers/isolated thunderstorms with a better chance for widespread rain showers/thunderstorms after 5pm and into the late evening, through 4am with lingering rain showers possible through daybreak Thursday. - Similar to last night, excess low-level moisture combined with a decent upper-level disturbance will result in a good chance for moderate to heavy rainfall this evening. Prime time for heavy rainfall will be between 5pm-2am. Storm motions will generally be W/NW to E/SE this evening, with anchored storms and some erratic storm motions possible along outflow boundaries effectively increasing chances for heavy rainfall. - Overnight lows will drop into the upper 50's to low 60's with continued rainfall chances through daybreak Thursday, however the intensity of storms will diminish significantly after 2am Thursday. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers and weak thunderstorms will produce rainfall amounts of a 0.1 to 0.4" in 10-30 minutes. Moderate to brief heavy rain showers/thunderstorms will produce 0.4-1.0" in 10-30 minutes. WORST CASE SCENARIO: A stronger, stationary thunderstorm is able to develop with the potential to produce rainfall rates of 1.0-2.0" in 30-60 minutes. A LOOK AHEAD: This active weather pattern will hold into the weekend with storm chances picking up both Thursday and Friday. Thursday will have the greatest threat for continued heavy rainfall during the afternoon and evening as another disturbance moves into the region at that time. Friday's rain chances decrease slightly, however the threat for heavy rainfall will likely remain with a good chance for afternoon and evening rain showers with a slight chance for overnight rain into Saturday. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 500 PM TO 400 AM THU 0.1" (80%) to 0.4" (50%) to 1.0" (30%) HIGH Arapahoe 500 PM TO 400 AM THU 0.1" (80%) to 0.4" (50%) to 1.0" (30%) HIGH Boulder 500 PM TO 400 AM THU 0.1" (80%) to 0.4" (50%) to 1.0" (30%) HIGH Broomfield 500 PM TO 400 AM THU 0.1" (80%) to 0.4" (50%) to 1.0" (30%) HIGH Denver 500 PM TO 400 AM THU 0.1" (80%) to 0.4" (50%) to 1.0" (30%) HIGH Douglas 500 PM TO 400 AM THU 0.1" (80%) to 0.4" (50%) to 1.0" (30%) HIGH Jefferson 500 PM TO 400 AM THU 0.1" (80%) to 0.4" (50%) to 1.0" (30%) HIGH Foothills above 6500ft       Boulder 500 PM TO 400 AM THU 0.1" (90%) to 0.4" (60%) to 1.0" (40%) HIGH Douglas 500 PM TO 400 AM THU 0.1" (90%) to 0.4" (60%) to 1.0" (40%) HIGH Jefferson 500 PM TO 400 AM THU 0.1" (90%) to 0.4" (60%) to 1.0" (40%) HIGH MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]