Flash Flood Prediction Program

-	Temperatures will remain rather warm today with highs reaching the lower 90's over the plains with upper 70's and 80's in the Front Range foothills. SSW flow aloft is transporting moisture into the area in the upper levels of the atmosphere and will help to produce widely scattered thunderstorms over the District this afternoon and early evening.
-	Surface moisture is only modest resulting the storms that develop today producing mainly light to brief moderate rain, but an isolated brief heavy rain shower cannot be ruled out. Best chances for storms today will be from 3-9pm over the plains. Storms will move from SW to NE at 15-20mph.
-	After 9pm this evening the majority of the shower and thunderstorm activity is expected to be coming to an end with a slight chance to experience an isolated rain shower overnight as moisture will be on the increase at the surface and aloft.

STORM RAINFALL POTENTIAL AND DURATION: Typical weak to moderate thunderstorms will produce a trace to 0.3". Stronger thunderstorms will have the potential to produce 0.3-0.6" in 10-30 minutes. Supplemental QPF is available at https://qpf.udfcd.org

WORST CASE SCENARIO: A slow moving gust front induced thunderstorm may be able to tap into higher moisture with the potential to produce up to 1.0" of rain in 45-60 minutes.

A LOOK AHEAD: A monsoon moisture plume is expected to pass directly overhead on Friday resulting in widespread to numerous showers and thunderstorms in the afternoon and evening. Thunderstorms will be very capable of producing heavy rainfall that may lead to excessive runoff and possibly flash flooding.

Location	Prime Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	300 PM TO 900 PM	Trace (80%) to 0.2" (30%) to 0.5" (10%)	LOW
Arapahoe	300 PM TO 900 PM	Trace (80%) to 0.2" (30%) to 0.5" (10%)	LOW
Boulder	300 PM TO 900 PM	Trace (80%) to 0.2" (30%) to 0.5" (10%)	LOW
Broomfield	300 PM TO 900 PM	Trace (80%) to 0.2" (30%) to 0.5" (10%)	LOW
Denver	300 PM TO 900 PM	Trace (80%) to 0.2" (30%) to 0.5" (10%)	LOW
Douglas	200 PM TO 900 PM	Trace (80%) to 0.2" (30%) to 0.5" (10%)	LOW
Jefferson	200 PM TO 900 PM	Trace (80%) to 0.2" (30%) to 0.5" (10%)	LOW
Foothills above 6500ft
Boulder	100 PM TO 900 PM	Trace (90%) to 0.2" (40%) to 0.5" (10%)	LOW
Douglas	100 PM TO 900 PM	Trace (90%) to 0.2" (40%) to 0.5" (10%)	LOW
Jefferson	100 PM TO 900 PM	Trace (90%) to 0.2" (40%) to 0.5" (10%)	LOW

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.