Time: 927 AM Sat June 8, 2024 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- Cooler today with a better chance for afternoon and early evening showers/isolated thunderstorms. Westerly flow aloft will dominate over the region today, leading to warm and dry conditions this morning. Dew points currently around 50 degrees will likely hold during the day today, likely enhancing the threat for brief heavy rainfall during the afternoon and early evening before skies gradually clear through the later evening. The best chance for any shower/thunderstorm activity within the District will be between 1-7pm with a few lingering showers possible through 9pm. The best chance for heavy rainfall will be during the initial round of storms, with storm intensities decreasing into the evening hours. Storm motions will be west to east between 15-20mph which will also limit point rainfall amounts. Good upper-level support suggests at least a moderate chance for severe weather today, mainly for gusty winds 60+ mph and hail up to 1.0” in diameter. Severe storms will also contain isolated heavy rainfall with the largest threat being a quick 0.5” in 10-15min rather than any long-lasting heavy rainfall. Skies will gradually clear later this evening with dry conditions expected through the overnight as temperatures drop into the mid to upper 50s on the plains with upper 40s to around 50 degrees along the foothills. STORM RAINFALL POTENTIAL AND DURATION: Typical showers and isolated thunderstorms will produce a 0.05-0.30” total in 10-30 minutes. A moderate to strong/severe shower/thunderstorm will produce 0.30-0.60” total in 10-30 minutes. WORST CASE SCENARIO: A strong, stationary thunderstorm, or training of thunderstorm cells will have the potential to produce up to 1.20” total in under 60 minutes. A LOOK AHEAD: Similar conditions remain in place on Sunday. However, slightly less overall moisture will decrease storm potential slightly across the I-25 corridor. The timing of storm chances will once again be in the early afternoon, lasting into the early evening before any shower activity clears out for the rest of the evening and overnight. Depending on the amount of residual moisture from today will dictate the threat level tomorrow with at least a LOW chance for Messages at this time. Minimal overall change Monday as high temperatures remain in the low to mid 80s. A continued chance for afternoon and early evening showers/thunderstorms, with a slight chance some of those storms produce brief heavy rainfall, likely keeping a LOW chance for Messages. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 100 PM TO 700 PM 0.05" (90%) to 0.3" (60%) to 0.6" (30%) MOD Arapahoe 100 PM TO 700 PM 0.05" (90%) to 0.3" (60%) to 0.6" (30%) MOD Boulder 100 PM TO 700 PM 0.05" (80%) to 0.3" (40%) to 0.6" (20%) MOD Broomfield 100 PM TO 700 PM 0.05" (80%) to 0.3" (40%) to 0.6" (20%) MOD Denver 100 PM TO 700 PM 0.05" (90%) to 0.3" (60%) to 0.6" (30%) MOD Douglas 100 PM TO 700 PM 0.05" (80%) to 0.3" (40%) to 0.6" (20%) MOD Jefferson 100 PM TO 700 PM 0.05" (80%) to 0.3" (40%) to 0.6" (20%) MOD Foothills above 6500ft       Boulder 100 PM TO 700 PM 0.05" (70%) to 0.3" (35%) to 0.6" (15%) LOW Douglas 100 PM TO 700 PM 0.05" (70%) to 0.3" (35%) to 0.6" (15%) LOW Jefferson 100 PM TO 700 PM 0.05" (70%) to 0.3" (35%) to 0.6" (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]