Flash Flood Prediction Program

-	Message 1's have been issued for the entire District and will be valid until 10:00pm this evening.
-	Temperatures have remained on the cool side today over the District hindering thunderstorm development up to this point but an approaching upper level disturbance is expected override the lack of heat and generate showers and thunderstorms later this afternoon and evening. The strength of the storms remains in question but even a moderate thunderstorm will have the potential to produce brief heavy rainfall. 1-2 rounds of showers and thunderstorms are expected through 10pm.
-	Individual thunderstorms will move from NW to SE at around 15mph. A briefly anchored strong thunderstorm or slower moving large thunderstorm will contain the greatest potential to produce long duration heavy rainfall that may lead to excessive runoff and possibly flash flooding.

STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak thunderstorms will produce 0.1-0.5" in 10-30 minutes. Moderate to strong thunderstorms will have the potential to produce 0.5-1.3" in 10-30 minutes.

WORST CASE SCENARIO: A briefly anchored thunderstorm or slower moving large thunderstorm may result in up to 2.5" of heavy rain in 45-60 minutes.

County	Message	Valid Times	Prime Time
Boulder County	1	Current TO 1000 PM	330 PM TO 930 PM
Jefferson County	1	Current TO 1000 PM	330 PM TO 930 PM
Broomfield County	1	Current TO 1000 PM	330 PM TO 930 PM
Douglas County	1	Current TO 1000 PM	330 PM TO 930 PM
Adams County	1	Current TO 1000 PM	330 PM TO 930 PM
Denver County	1	Current TO 1000 PM	330 PM TO 930 PM
DIA	1	Current TO 1000 PM	330 PM TO 930 PM
Arapahoe County	1	Current TO 1000 PM	330 PM TO 930 PM
the City of Aurora	1	Current TO 1000 PM	330 PM TO 930 PM
Arvada	1	Current TO 1000 PM	330 PM TO 930 PM
Wheat Ridge	1	Current TO 1000 PM	330 PM TO 930 PM
Lakewood	1	Current TO 1000 PM	330 PM TO 930 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	330 PM TO 1000 PM	0.1" (80%) to 0.5" (40%) to 1.3" (20%)	ISSUED
Arapahoe	330 PM TO 1000 PM	0.1" (80%) to 0.5" (40%) to 1.3" (20%)	ISSUED
Broomfield	330 PM TO 1000 PM	0.1" (80%) to 0.5" (40%) to 1.3" (20%)	ISSUED
Denver	330 PM TO 1000 PM	0.1" (80%) to 0.5" (40%) to 1.3" (20%)	ISSUED
Boulder	300 PM TO 1000 PM	0.1" (90%) to 0.5" (50%) to 1.3" (25%)	ISSUED
Douglas	300 PM TO 1000 PM	0.1" (90%) to 0.5" (50%) to 1.3" (25%)	ISSUED
Jefferson	300 PM TO 1000 PM	0.1" (90%) to 0.5" (50%) to 1.3" (25%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 1000 PM WED	0.1" (100%) to 0.5" (60%) to 1.3" (30%)	ISSUED
Douglas	Current TO 1000 PM WED	0.1" (100%) to 0.5" (60%) to 1.3" (30%)	ISSUED
Jefferson	Current TO 1000 PM WED	0.1" (100%) to 0.5" (60%) to 1.3" (30%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.