Time: 938 AM Sat August 10, 2024 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- Warmer, scattered thunderstorms afternoon and evening Warmer temperatures and similar moisture profiles will allow for more organized thunderstorm development today, as opposed to the sporadic convection and showers present the past few days. Drier air aloft, decent surface moisture (forecasted afternoon dewpoints in low 50s), and fast-moving upper level flow will support development of thunderstorms over the high country west of the District in the early afternoon. Thunderstorms today will move from the west/northwest to the east/southeast at 15-20mph and, once reaching the foothills and urban corridor, will exist in an environment conducive to severe thunderstorm development. Heavy rainfall, hail, and gusty outflow winds to 60mph will be possible with the stronger storms today, though these conditions are more likely to develop on the plains east of the District. Atmospheric recovery appears likely today, meaning multiple rounds of storms are possible throughout the afternoon, evening, and into the early overnight hours. Skies will clear through the pre-sunrise hours of Tuesday, but a strong shortwave disturbance and synoptic-scale lift from the right entrance region of a jet streak over the High Plains create chances for light morning showers Sunday. STORM RAINFALL POTENTIAL AND DURATION: Typical showers and thunderstorms will produce 0.10"-0.30" total in 10-30 minutes. A stronger or slower-moving thunderstorm will produce up to 0.30"-1.00" total in 10-30 minutes WORST CASE SCENARIO: An anchored/stationary thunderstorm, or training of thunderstorms along a boundary, may be capable of producing 2.00" of rainfall in up to 60 minutes. A LOOK AHEAD: Slightly lower thunderstorm and message issuance potential Sunday as drier air fills in from the upper atmosphere after morning shower chances. Increase in chances again Monday as a strong shortwave ahead of a deepening trough over the Pacific Northwest and continued monsoonal moisture transport create higher chances of thunderstorm development. A gradual warming and drying trend begins Tuesday. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Arapahoe 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Boulder 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Broomfield 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Denver 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Douglas 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Jefferson 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Foothills above 6500ft       Boulder 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Douglas 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) LOW Jefferson 200 PM TO 1100 PM 0.1" (70%) to 0.3" (40%) to 1" (10%) 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]