Time: 921 AM Mon June 10, 2024 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- Slightly warmer today with another chance for afternoon and early evening showers with possible isolated moderate to strong thunderstorms. High-pressure continues to build over the District this morning, slowly moving easterly resulting in upper-level winds shifting northwesterly this afternoon. This shift in upper-level dynamics will effectively help storm motions today from the NW to SE between 10-20mph, limiting any long-lasting moderate to heavy rainfall. However, with dew points still in the mid to upper 50s, a couple of stronger storms will have the potential to produce outflow boundaries today, bringing another chance for some erratic/stationary storm motions leading to another chance for a few isolated heavy showers this afternoon and into the early evening. The best chance for storm activity this afternoon and early evening will be between 2-9pm. The initial round of storms will likely be the strongest during the afternoon today, bringing the best chance of impactful rainfall producing storms, possibly severe, with another chance for an additional round of showers in the evening before skies clear through the overnight. Temperatures overnight will drop into the upper 50s to around 60 degrees 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 0.05-0.40” total in 10-30 minutes. A moderate to strong/severe shower/thunderstorm will produce 0.40-0.80” total in 10-30 minutes. WORST CASE SCENARIO: A strong, stationary thunderstorm, or training of thunderstorm cells will have the potential to produce up to 1.60” total in under 30 minutes. A LOOK AHEAD: Conditions start to dry out Tuesday with just a typical chance for springtime afternoon showers/isolated thunderstorms. Wednesday is expected to be even drier with minimal, if any, chance for precipitation at this time across the District. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Arapahoe 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Boulder 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Broomfield 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Denver 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Douglas 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Jefferson 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Foothills above 6500ft       Boulder 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Douglas 200 PM TO 900 PM 0.05" (80%) to 0.4" (40%) to 0.8" (20%) MOD Jefferson 200 PM TO 900 PM 0.05" (80%) to 0.4" (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]