Flash Flood Prediction Program

Time: 856 AM Mon May 16, 2022 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- ANOTHER WARM DAY WITH A SLIGHT CHANCE FOR HIGH-BASED AFTERNOON RAIN/ISOLATED THUNDERSTORMS - After several dry days, a change in the weather pattern this week will bring rain chances across the District. Mild and dry to start the day today with high temperatures expected in the low to mid 80's on the plains with low to mid 70's along the foothills. Best chance for rain shower activity today will be from noon until 6pm with skies gradually clearing this evening and through the overnight. - Above average temperatures this afternoon, combined with dew points in the low to mid 30's will result in high-based rain showers with minimal precipitation expected as most rainfall will struggle to reach the surface. A few isolated thunderstorms cannot be completely ruled out, favoring the foothills and along the Palmer Divide which could also produce a few lightning strikes along with a slightly better chance for impactful rainfall. - Rainfall chances taper off after 6pm as overnight lows drop into low to mid 50's on the plains, with mid to upper 40's along the foothills. Mild and dry conditions are expected through daybreak Tuesday. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers/isolated thunderstorms will produce a trace to 0.1" of rainfall in 10-30 minutes. Weak to moderate thunderstorms will have the potential to produce rainfall rates of 0.1-0.3" in 10-30 minutes. WORST CASE SCENARIO: A moderate to strong thunderstorm is able to develop, or training of thunderstorms with the potential for moderate to brief heavy rainfall of 0.3-0.6" in 30-60 minutes. A LOOK AHEAD: Similar conditions in place for Tuesday with another chance for high-based afternoon rain/isolated thunderstorms with minimal rainfall expected at this time. An uptick in moisture Wednesday will result in a better chance for widespread afternoon/eve rain/thunderstorms with a low chance at this time for a heavy rainfall threat. A break in the pattern Thursday with mostly dry conditions throughout the day, with a chance for late evening rain showers with off and on rain showers through the day Friday with a chance for rain/mix and possibly some snow Friday evening and into Saturday morning. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 1200 PM TO 600 PM Trace (30%) to 0.1" (20%) to 0.3" (5%) NONE Arapahoe 1200 PM TO 600 PM Trace (30%) to 0.1" (20%) to 0.3" (5%) NONE Boulder 1200 PM TO 600 PM Trace (30%) to 0.1" (20%) to 0.3" (5%) NONE Broomfield 1200 PM TO 600 PM Trace (30%) to 0.1" (20%) to 0.3" (5%) NONE Denver 1200 PM TO 600 PM Trace (30%) to 0.1" (20%) to 0.3" (5%) NONE Douglas 1200 PM TO 600 PM Trace (30%) to 0.1" (20%) to 0.3" (5%) NONE Jefferson 1200 PM TO 600 PM Trace (30%) to 0.1" (20%) to 0.3" (5%) NONE Foothills above 6500ft       Boulder 1200 PM TO 600 PM Trace (50%) to 0.1" (40%) to 0.3" (10%) NONE Douglas 1200 PM TO 600 PM Trace (50%) to 0.1" (40%) to 0.3" (10%) NONE Jefferson 1200 PM TO 600 PM Trace (50%) to 0.1" (40%) to 0.3" (10%) NONE MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]