Flash Flood Prediction Program

-	Message 1's have been issued for the entire District and will be valid from 12:30-8:00pm.
-	Thunderstorms have initiated over the higher terrain W of the District and are expected to slowly propagate eastward moving into the District through the early afternoon. Prime time for thunderstorms over the plains will be from 2-7pm and starting a bit earlier over the foothills.
-	Thunderstorms will be very slow moving from SW to NE at 5-10mph or less. Strong thunderstorms may remain nearly stationary or move erratically along outflow boundaries/gust fronts. Thunderstorms that develop today will be very capable of producing heavy rainfall that may lead to excessive runoff and possibly flash flooding.

STORM RAINFALL POTENTIAL AND DURATION: Typical weak to moderate thunderstorms will produce 0.1-0.4" in 10-30 minutes. Strong thunderstorms will have the potential to produce 0.4-1.2" in 10-30 minutes.

WORST CASE SCENARIO: A large thunderstorm or stationary strong thunderstorm may produce up to 2.5" of rain in 45-75 minutes.

County	Message	Valid Times	Prime Time
Lakewood	1	1230 PM TO 800 PM	200 PM TO 700 PM
Wheat Ridge	1	1230 PM TO 800 PM	200 PM TO 700 PM
Arvada	1	1230 PM TO 800 PM	200 PM TO 700 PM
Arapahoe County	1	1230 PM TO 800 PM	200 PM TO 700 PM
the City of Aurora	1	1230 PM TO 800 PM	200 PM TO 700 PM
DIA	1	1230 PM TO 800 PM	200 PM TO 700 PM
Douglas County	1	1230 PM TO 800 PM	130 PM TO 700 PM
Adams County	1	1230 PM TO 800 PM	200 PM TO 700 PM
Denver County	1	1230 PM TO 800 PM	200 PM TO 700 PM
Broomfield County	1	1230 PM TO 800 PM	200 PM TO 700 PM
Jefferson County	1	1230 PM TO 800 PM	130 PM TO 700 PM
Boulder County	1	1230 PM TO 800 PM	130 PM TO 700 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	200 PM TO 800 PM	0.1" (80%) to 0.4" (40%) to 1.3" (20%)	ISSUED
Arapahoe	200 PM TO 800 PM	0.1" (80%) to 0.4" (40%) to 1.3" (20%)	ISSUED
Broomfield	200 PM TO 800 PM	0.1" (80%) to 0.4" (40%) to 1.3" (20%)	ISSUED
Denver	200 PM TO 800 PM	0.1" (80%) to 0.4" (40%) to 1.3" (20%)	ISSUED
Boulder	100 PM TO 800 PM	0.1" (80%) to 0.4" (40%) to 1.3" (20%)	ISSUED
Douglas	100 PM TO 800 PM	0.1" (80%) to 0.4" (40%) to 1.3" (20%)	ISSUED
Jefferson	100 PM TO 800 PM	0.1" (80%) to 0.4" (40%) to 1.3" (20%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 800 PM SAT	0.1" (90%) to 0.4" (50%) to 1.3" (15%)	ISSUED
Douglas	Current TO 800 PM SAT	0.1" (90%) to 0.4" (50%) to 1.3" (15%)	ISSUED
Jefferson	Current TO 800 PM SAT	0.1" (90%) to 0.4" (50%) to 1.3" (15%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.