Flash Flood Prediction Program

Time: 826 AM Mon July 4, 2022 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- HOT TODAY WITH ANOTHER CHANCE FOR AFTERNOON & EVE RAIN SHOWERS/ISOLATED THUNDERSTORMS - Temperatures will increase today with highs in the low to mid 90's on the plains with mid to upper 80's along the foothills. Not much change in the overall weather pattern today with another chance for afternoon and evening rain showers/isolated thunderstorms. Currently temperatures are already in the low to mid 70's across the plains. Currently dew points remain slightly elevated with mid 40's to low 50's, however, these dew points should mix out through the morning into the low to mid 40's. There is a chance the excess surface moisture remain in place through this morning and into the afternoon, therefor, a low chance will remain for Message 1 potential, favoring areas along the foothills at this time. - Similar to yesterday, rain showers/isolated thunderstorms are expected to develop along the higher terrain between 12-2pm with rain showers/isolated thunderstorms possible in the District between 1-9pm. Storm motions will generally be west to east, between 10-20mph with peak storm chances between 4-8pm. A round or two of storms will be possible today, with the first round bringing the best chance for moderate to brief heavy rainfall at this time, with additional storm development possible from outflow boundaries, especially if stronger storms are able to develop along the Wyoming Ridge and the Palmer Divide. - Elevated surface moisture and good daytime heating will be in place for a slight chance of moderate to brief heavy rainfall today resulting in a low risk for Message issuance, however if low-level moisture mixes out before adequate heating takes place it will help keep the moderate to heavy rainfall at bay. Overnight lows excepted to drop into the low to mid 60's with mild conditions expected into daybreak Tuesday. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers and weak thunderstorms will produce TR-0.2" of rain in 10-30 minutes. Moderate to briefly strong thunderstorms will have the potential to produce rainfall rates of 0.2-0.5" in 10-30 minutes. WORST CASE SCENARIO: Strong, slower moving thunderstorms if able to develop will have the potential to produce heavy rainfall rates of 0.5-1.0" in 10-30 minutes and up to 2.0" in 45-75 minutes. A LOOK AHEAD: Similar conditions remain through the week with high temperatures holding around 90 degrees through Friday. A chance for afternoon and evening rain showers isolated thunderstorms Tuesday through Friday as well. Tomorrow's rain showers/isolated thunderstorms will be similar to today with a better chance of widespread rain showers/thunderstorms on Wednesday. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 100 PM TO 900 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Arapahoe 100 PM TO 900 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Boulder 100 PM TO 900 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Broomfield 100 PM TO 900 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Denver 100 PM TO 900 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Douglas 100 PM TO 900 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Jefferson 100 PM TO 900 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Foothills above 6500ft       Boulder 1200 PM TO 800 PM Trace (75%) to 0.2" (50%) to 0.5" (25%) LOW Douglas 1200 PM TO 800 PM Trace (75%) to 0.2" (50%) to 0.5" (25%) LOW Jefferson 1200 PM TO 800 PM Trace (75%) to 0.2" (50%) to 0.5" (25%) 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]