Flash Flood Prediction Program

Time: 859 AM Thu July 14, 2022 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- ANOTHER HOT DAY WITH SCATTERED HIGH-BASED AFTERNOON RAIN SHOWERS/ISOLATED THUNDERSTORMS - Northwesterly flow aloft will turn westerly today effectively increasing today's high temperatures well into the 90's on the plains with upper 80's to low 90's along the foothills. Similar conditions to yesterday with a chance for afternoon and early evening scattered high-based rain showers/isolated thunderstorms. Once again there will be a good chance showers stay minimal, however with mid to upper 40's dew points currently, a low chance for moderate to brief heavy rainfall will remain, with increased chances if low-level moisture does not mix out efficiently through the rest of the morning. - Initial storm development along the higher terrain will likely begin between 1 and 3pm with the best chance for rain showers/isolated thunderstorms in the District between 3-8pm this evening. Typical thunderstorms today will produce light to brief moderate rain and breezy winds. Storm motions will be fairly brisk, between 10-15mph from the W to E, however a gust front, or outflow boundary has the potential to produce storms that anchor in place for an extended period of time. Storms are expected to strengthen E of the I-25 corridor possibly becoming strong over the plains, although the better chances for strong storms today should be well east of the District boundaries. - Skies will gradually clear this evening with mild and dry conditions expected through the overnight and into Thursday. Overnight lows will dip into the mid to upper 60's on the plains with mid to upper 50's along the foothills. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers and weak thunderstorms will produce a trace to 0.2" of moisture. Moderate thunderstorms will have the potential to produce rainfall rates of 0.2-0.5" in 10-30 minutes. WORST CASE SCENARIO: Strong thunderstorms are able to develop with the potential to produce heavy rainfall of 0.4-1.0" in 10-30 minutes and up to 1.5" in 45-60 minutes. A LOOK AHEAD: A little more mid to upper-level moisture tomorrow will increase chances for afternoon and evening rain showers/isolated thunderstorms with a low to moderate chance storms produce heavy rainfall at this time. Temperatures start to increase this weekend with highs flirting with triple digits. A slight chance will remain for a few scattered rain showers/isolated thunderstorms Saturday with dry conditions likely Sunday. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Arapahoe 200 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Boulder 200 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Broomfield 200 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Denver 200 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Douglas 200 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Jefferson 200 PM TO 800 PM Trace (50%) to 0.2" (25%) to 0.5" (10%) LOW Foothills above 6500ft       Boulder 200 PM TO 800 PM Trace (60%) to 0.2" (30%) to 0.5" (15%) LOW Douglas 200 PM TO 800 PM Trace (60%) to 0.2" (30%) to 0.5" (15%) LOW Jefferson 200 PM TO 800 PM Trace (60%) to 0.2" (30%) to 0.5" (15%) 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]