Time: 900 PM Thu August 20, 2020 Forecaster: Justin Brooks

Heavy Precipitation Outlook
Flash Flood Prediction Program

A LATE EVENING ROUND OF SHOWERS/ISOLATED THUNDERSTORMS HAVE MOVED INTO THE DISTRICT
-An evening disturbance is moving through the District currently resulting in showers and thunderstorms along northern portions of the District.
-These storms are moving relatively quickly at 15-20 mph towards the E/SE. Rain showers and isolated thunderstorms will be possible through midnight. With dew points in the mid 40's, isolated moderate to brief heavy rain is possible under stronger cells that develop.
-By midnight skies will gradually clear as temperatures drop into the 60's.
STORM RAINFALL POTENTIAL AND DURATION: Weak thunderstorms will produce a trace to 0.1" in 10-30min. A moderate rain shower/thunderstorm could produce 0.1-0.4" in 10-30min. Supplemental QPF is available at https://qpf.udfcd.org

WORST CASE SCENARIO: A large, slower moving thunderstorm formed off an outflow boundary may produce rainfall amounts of up to 0.8" in 45-60 minutes.

A LOOK AHEAD: Drier conditions in store for Friday and Saturday with high temperatures remaining in the mid to upper 90's. A very slight chance Sunday and Monday for an isolated afternoon rain shower/thunderstorm.

Location Prime Time 30-Minute Rainfall
and % Probability
Message
Potential
Plains      
Adams Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (10%) LOW
Arapahoe Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (5%) LOW
Boulder Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (10%) LOW
Broomfield Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (10%) LOW
Denver Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (10%) LOW
Douglas Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (10%) LOW
Jefferson Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (5%) LOW
Foothills above 6500ft      
Boulder Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (5%) LOW
Douglas Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (5%) LOW
Jefferson Current TO 1000 PM THU
Trace (50%) to 0.4" (20%) to 0.8" (5%) LOW
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.