Time: 752 PM Thu June 8, 2023 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S ISSUED FOR THE ENTIRE DISTRICT Message 1’s have been issued for the entire District and will be valid until midnight. Thunderstorms are prevalent over the Front Range foothills and upper level steering winds will push these storms onto the plains as the evening progresses. These thunderstorms may dissipate on approach but may also produce an outflow boundary, or a new trigger for thunderstorm development further eastward within the District. The scenario will play out over the next few hours… Should a strong thunderstorm develop, it will be capable of producing heavy rainfall and hail. With the ground at or near saturation in many areas of the District it may not take as much rain to produce excessive runoff and possibly flash flooding. STORM RAINFALL POTENTIAL AND DURATION: Weak thunderstorms will produce rainfall amounts of 0.1-0.4”. Moderate to strong thunderstorms will produce rainfall rates of 0.4-1.0” in 10-30 minutes. WORST CASE SCENARIO: A slower moving strong thunderstorm or training of thunderstorm cells may result in up to 1.8” of rain in 45-75 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Boulder County 1 Current TO 1159 PM 830 PM TO 1100 PM Jefferson County 1 Current TO 1159 PM 830 PM TO 1100 PM Broomfield County 1 Current TO 1159 PM 830 PM TO 1100 PM Douglas County 1 Current TO 1159 PM 830 PM TO 1100 PM Adams County 1 Current TO 1159 PM 830 PM TO 1100 PM Denver County 1 Current TO 1159 PM 830 PM TO 1100 PM DIA 1 Current TO 1159 PM 830 PM TO 1100 PM Arapahoe County 1 Current TO 1159 PM 830 PM TO 1100 PM the City of Aurora 1 Current TO 1159 PM 830 PM TO 1100 PM Arvada 1 Current TO 1159 PM 830 PM TO 1100 PM Wheat Ridge 1 Current TO 1159 PM 830 PM TO 1100 PM Lakewood 1 Current TO 1159 PM 830 PM TO 1100 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1159 PM THU 0.1" (75%) to 0.4" (40%) to 1" (15%) ISSUED Arapahoe Current TO 1159 PM THU 0.1" (75%) to 0.4" (40%) to 1" (15%) ISSUED Boulder Current TO 1159 PM THU 0.1" (80%) to 0.4" (50%) to 1" (20%) ISSUED Broomfield Current TO 1159 PM THU 0.1" (80%) to 0.4" (50%) to 1" (20%) ISSUED Denver Current TO 1159 PM THU 0.1" (75%) to 0.4" (40%) to 1" (15%) ISSUED Douglas Current TO 1159 PM THU 0.1" (80%) to 0.4" (50%) to 1" (20%) ISSUED Jefferson Current TO 1159 PM THU 0.1" (80%) to 0.4" (50%) to 1" (20%) ISSUED Foothills above 6500ft       Boulder Current TO 1159 PM THU 0.1" (90%) to 0.4" (60%) to 1" (25%) ISSUED Douglas Current TO 1159 PM THU 0.1" (90%) to 0.4" (60%) to 1" (25%) ISSUED Jefferson Current TO 1159 PM THU 0.1" (90%) to 0.4" (60%) to 1" (25%) ISSUED MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]