Time: 730 PM Sat August 14, 2021 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- A CHANCE FOR STORMS HAS INCREASED SLIGHTLY THIS EVENING - A disturbance from the NW is currently moving into the District at this time, which has increased the potential for storms this evening. - Dewpoint are fairly wide spread over the District with upper 30's to low 40's in southern and eastern areas. However, to the north and northwest portions of the District, increased surface moisture currently around the boulder area with dew points in the low to mid 50's suggest the potential for brief heavy rainfall as storms move through the region over the next few hours. - At this time storm motions are relatively brisk from the NW to SE between 10-20mph which will help limit point rainfall amounts. However, stronger storms could produce outflow boundaries which may trigger slower moving or stationary storms with the potential for isolated brief heavy rainfall. STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak thunderstorms will produce a trace to 0.2” of rain in 10-30 minutes. Moderate thunderstorms will have the potential to produce 0.2-0.6" of rain in 10-30 minutes. WORST CASE SCENARIO: A slow moving or stationary strong thunderstorms has the potential to produce 1.2" of rainfall in 45-75 minutes. A LOOK AHEAD: Similar conditions remain in place tomorrow with chances for afternoon and early evening rain showers/isolated thunderstorms. Temperatures will be in the mid to upper 80's. Monday will likely dry out as high-pressure returns leading to mostly sunny skies with highs around 90 degrees. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 1100 PM SAT Trace (60%) to 0.2" (30%) to 0.6" (15%) LOW Arapahoe Current TO 1100 PM SAT Trace (60%) to 0.2" (30%) to 0.6" (15%) LOW Boulder Current TO 1100 PM SAT Trace (60%) to 0.2" (30%) to 0.6" (15%) LOW Broomfield Current TO 1100 PM SAT Trace (60%) to 0.2" (30%) to 0.6" (15%) LOW Denver Current TO 1100 PM SAT Trace (60%) to 0.2" (30%) to 0.6" (15%) LOW Douglas Current TO 1100 PM SAT Trace (75%) to 0.2" (40%) to 0.6" (20%) LOW Jefferson Current TO 1100 PM SAT Trace (75%) to 0.2" (40%) to 0.6" (20%) LOW Foothills above 6500ft       Boulder Current TO 1100 PM SAT Trace (80%) to 0.2" (50%) to 0.6" (30%) LOW Douglas Current TO 1100 PM SAT Trace (80%) to 0.2" (50%) to 0.6" (30%) LOW Jefferson Current TO 1100 PM SAT Trace (80%) to 0.2" (50%) to 0.6" (30%) 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]