Time: 833 AM Sat August 6, 2022 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- AFTERNOON AND EVENING RAIN SHOWERS/THUNDERSTORMS WITH A DECENT CHANCE FOR ISOLATED HEAVY RAIN - Excess surface moisture with dew points in the mid to upper 50's currently will likely not mix out well through the morning. Combined with adequate heating today with highs in the low 90's this afternoon, along with a weak disturbance moving through in the early afternoon will result in a good chance for rain showers/thunderstorms, some of which may contain brief heavy rainfall. - The first signs of storm activity will form along the higher terrain between noon-2pm with storms moving into the District between 2-4pm with a couple of rounds of storm chances through sunset with moderate to heavy rain showers tapering off by 9pm this evening. Typical storm motions will be from W/SW to E/NE between 10-15mph helping limit point rainfall amounts, however, a good chance additional storms develop along outflow boundaries which will have stationary and/or erratic behavior leading to an increased chance for a heavy rainfall threat today. - Storms today may also become severe with strong winds around 60mph with hail up to 1.5". Stronger storms will likely favor areas east of I-25 this afternoon and evening. A cold front will move through the region during the overnight hours, keeping a chance for scattered rain showers through daybreak Sunday, however the intensity and chance for heavy rain should diminish after sunset tonight. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers/thunderstorms will produce 0.1-0.4" in 10-30 minutes. Moderate to strong thunderstorms will have the potential to produce 0.4-1.2" in 10-30 minutes. WORST CASE SCENARIO: A strong anchored thunderstorm or a slower moving large thunderstorm may result in rainfall rates up to 2.8" in 45-75 minutes. A LOOK AHEAD: Cooler tomorrow behind the cold front that moves through the region through the overnight tonight. This cold front will greatly dictate the strength of storms Sunday as cooler temperatures will likely limit heavy rainfall activity, however, with lots of available moisture and good upper-level support, the threat for heavy rainfall will remain elevated at this time. Best chance for heavy rainfall tomorrow will be in the afternoon to early evening where daytime heating is at its strongest. Rain showers start to taper off Sunday evening with conditions drying out into Monday morning. A chance remains for afternoon/evening rain showers/isolated thunderstorms Monday, with a low chance for a heavy rainfall threat at this time. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 300 PM TO 900 PM 0.1" (80%) to 0.4" (40%) to 1.2" (20%) HIGH Arapahoe 300 PM TO 900 PM 0.1" (80%) to 0.4" (40%) to 1.2" (20%) HIGH Boulder 300 PM TO 900 PM 0.1" (85%) to 0.4" (45%) to 1.2" (25%) HIGH Broomfield 300 PM TO 900 PM 0.1" (80%) to 0.4" (40%) to 1.2" (20%) HIGH Denver 300 PM TO 900 PM 0.1" (80%) to 0.4" (40%) to 1.2" (20%) HIGH Douglas 300 PM TO 900 PM 0.1" (85%) to 0.4" (45%) to 1.2" (25%) HIGH Jefferson 300 PM TO 900 PM 0.1" (85%) to 0.4" (45%) to 1.2" (25%) HIGH Foothills above 6500ft       Boulder 300 PM TO 900 PM 0.1" (90%) to 0.4" (50%) to 1.2" (30%) HIGH Douglas 300 PM TO 900 PM 0.1" (90%) to 0.4" (50%) to 1.2" (30%) HIGH Jefferson 300 PM TO 900 PM 0.1" (90%) to 0.4" (50%) to 1.2" (30%) 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]