Time: 545 PM Sat July 3, 2021 Forecaster: Brad Simmons ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1'S CONTINUE VALID/HEAVY RAINFALL THREAT DECREASING - Message 1's will continue valid for the entire District until 8:30pm although the threat for heavy rainfall is decreasing as time wears on. - The outflow boundary that had the potential to produce thunderstorms with heavy rainfall only resulted in weak to briefly moderate thunderstorm activity over the District. Stronger storms have developed south along this same boundary but no longer poses a threat locally. Another boundary is currently moving through the District and is not producing any meaningful storm activity and this trend is expected to continue. - Most of the shower and any thunderstorm activity is expected to remain over the higher terrain and south of the District into the evening, however if a thunderstorm is able to develop over the plains it would be capable of producing briefly heavy rain. STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak thunderstorms will produce a trace to 0.2" of rain. Moderate to strong thunderstorms will have the potential to produce 0.3-0.8" in 10-30 minutes. WORST CASE SCENARIO: A stationary strong thunderstorm may result in up to 1.6" in 45-60 minutes. COUNTY MESSAGE VALID TIMES PRIME TIME Wheat Ridge 1 Current TO 830 PM 300 PM TO 730 PM Lakewood 1 Current TO 830 PM 300 PM TO 730 PM Arvada 1 Current TO 830 PM 300 PM TO 730 PM the City of Aurora 1 Current TO 830 PM 300 PM TO 730 PM DIA 1 Current TO 830 PM 300 PM TO 730 PM Arapahoe County 1 Current TO 830 PM 300 PM TO 730 PM Denver County 1 Current TO 830 PM 300 PM TO 730 PM Douglas County 1 Current TO 830 PM 300 PM TO 730 PM Adams County 1 Current TO 830 PM 300 PM TO 730 PM Broomfield County 1 Current TO 830 PM 300 PM TO 730 PM Jefferson County 1 Current TO 830 PM 300 PM TO 730 PM Boulder County 1 Current TO 830 PM 300 PM TO 730 PM County-specific Quantitative Precipitation Outlook PRECIPITATION TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 830 PM SAT Trace (40%) to 0.2" (20%) to 0.8" (10%) ISSUED Arapahoe Current TO 830 PM SAT Trace (40%) to 0.2" (20%) to 0.8" (10%) ISSUED Boulder Current TO 830 PM SAT Trace (60%) to 0.2" (30%) to 0.8" (10%) ISSUED Broomfield Current TO 830 PM SAT Trace (40%) to 0.2" (20%) to 0.8" (10%) ISSUED Denver Current TO 830 PM SAT Trace (40%) to 0.2" (20%) to 0.8" (10%) ISSUED Douglas Current TO 830 PM SAT Trace (60%) to 0.2" (30%) to 0.8" (10%) ISSUED Jefferson Current TO 830 PM SAT Trace (60%) to 0.2" (30%) to 0.8" (10%) ISSUED Foothills above 6500ft       Boulder Current TO 830 PM SAT Trace (80%) to 0.2" (50%) to 0.8" (15%) ISSUED Douglas Current TO 830 PM SAT Trace (80%) to 0.2" (50%) to 0.8" (15%) ISSUED Jefferson Current TO 830 PM SAT Trace (80%) to 0.2" (50%) to 0.8" (15%) 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]