Time: 940 AM Fri July 26, 2024 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- Slightly cooler with a chance for isolated afternoon showers/thunderstorms The high-pressure ridge that has anchored to the Four Corners region finally breaks down today. This will bring a chance for a few showers/thunderstorms this afternoon and into the early evening hours before clearing out during the late evening. Storms will initiate along the higher terrain around midday, moving onto the foothills between 1-2pm this afternoon with the best chance of storm activity within the District between 2-8pm. A couple of rounds of storms will be possible with the first round of storms likely having the best chance of moderate to brief heavy rainfall today. Generally, storm motions will be from west to east between 15-20mph which should help limit point rainfall amounts; However, stronger storms will have the potential to produce outflow boundaries resulting in some erratic storm motions. These outflow boundary storms will likely have the best potential for 0.30"-0.80” in under 30 minutes as these storms likely pulse up and rain themselves out. Between 8-9pm skies will gradually start to clear with mild and dry conditions expected overnight. Temperatures will drop into the low 60s for the plains with mid to upper 50s along the foothills. STORM RAINFALL POTENTIAL AND DURATION: Typical showers and thunderstorms will produce 0.05”-0.30” total in 10-30 minutes. A moderate to strong shower/thunderstorm will produce 0.30”-0.80” total in 10-30 minutes. WORST CASE SCENARIO: A strong stationary thunderstorm or training of thunderstorm cells will have the potential to produce 1.20” total in 30-60 minutes. A LOOK AHEAD: Not much overall change in the upper-level pattern tomorrow will bring another chance for afternoon and evening showers/thunderstorms. Slightly less overall moisture aloft will decrease chances for moderate to heavy rainfall for the District tomorrow. Similar high temperatures in the low 90s. The heat returns Sunday with highs jumping back into the upper 90s. A slight chance for high-based showers, mainly along the foothills in the afternoon and early evening. Hot and dry Monday with highs in the upper 90s. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 800 PM 0.05" (60%) to 0.3" (30%) to 0.8" (10%) LOW Arapahoe 200 PM TO 800 PM 0.05" (60%) to 0.3" (30%) to 0.8" (10%) LOW Boulder 200 PM TO 800 PM 0.05" (60%) to 0.3" (30%) to 0.8" (10%) LOW Broomfield 200 PM TO 800 PM 0.05" (60%) to 0.3" (30%) to 0.8" (10%) LOW Denver 200 PM TO 800 PM 0.05" (60%) to 0.3" (30%) to 0.8" (10%) LOW Douglas 200 PM TO 800 PM 0.05" (60%) to 0.3" (30%) to 0.8" (10%) LOW Jefferson 200 PM TO 800 PM 0.05" (60%) to 0.3" (30%) to 0.8" (10%) LOW Foothills above 6500ft       Boulder 200 PM TO 800 PM 0.05" (80%) to 0.3" (40%) to 0.8" (20%) MOD Douglas 200 PM TO 800 PM 0.05" (80%) to 0.3" (40%) to 0.8" (20%) MOD Jefferson 200 PM TO 800 PM 0.05" (80%) to 0.3" (40%) to 0.8" (20%) MOD MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]