Flash Flood Prediction Program

-	Message 1's have been issued for the entire District and will be valid until 8:00pm. An upper level disturbance is on the approach and is expected to produce 1-2 rounds of thunderstorms this afternoon. Stronger thunderstorms will be capable of producing brief heavy rainfall, gusty winds and hail.
-	Steering winds from SW to NE at 15-20mph will keep storms moving along at a brisk pace but stronger storms will be capable of producing heavy rainfall that may lead to excessive runoff. Favored areas for stronger storms looks to be along and E of I-25 where moisture is deeper. Storms are currently starting to fill in over NW portions of the District and will spread to the SE as the afternoon progresses.
-	After 7 or 8pm the main round or two of storms is expected to have pushed eastward with lingering more isolated light rain showers remaining possible until around 10pm. Beyond 10pm dry conditions are expected for the remainder of the evening/overnight period.

STORM RAINFALL POTENTIAL AND DURATION: Weak thunderstorms will produce 0.1-0.4" of rainfall in 10-30 minutes. Moderate to strong thunderstorms will have the potential to produce heavy rainfall of 0.4-1.2" in 10-30 minutes.

WORST CASE SCENARIO: Training of strong thunderstorm cells or a slower moving large thunderstorm may result in up to 2.4" of rainfall in 60-90 minutes.

County	Message	Valid Times	Prime Time
Boulder County	1	1200 PM TO 800 PM	100 PM TO 700 PM
Jefferson County	1	1200 PM TO 800 PM	100 PM TO 700 PM
Broomfield County	1	1200 PM TO 800 PM	100 PM TO 700 PM
Douglas County	1	1200 PM TO 800 PM	100 PM TO 700 PM
Adams County	1	1200 PM TO 800 PM	100 PM TO 700 PM
Denver County	1	1200 PM TO 800 PM	100 PM TO 700 PM
DIA	1	1200 PM TO 800 PM	100 PM TO 700 PM
Arapahoe County	1	1200 PM TO 800 PM	100 PM TO 700 PM
the City of Aurora	1	1200 PM TO 800 PM	100 PM TO 700 PM
Arvada	1	1200 PM TO 800 PM	100 PM TO 700 PM
Wheat Ridge	1	1200 PM TO 800 PM	100 PM TO 700 PM
Lakewood	1	1200 PM TO 800 PM	100 PM TO 700 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (25%)	ISSUED
Arapahoe	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (25%)	ISSUED
Boulder	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (20%)	ISSUED
Broomfield	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (20%)	ISSUED
Denver	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (25%)	ISSUED
Douglas	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (25%)	ISSUED
Jefferson	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (20%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (15%)	ISSUED
Douglas	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (15%)	ISSUED
Jefferson	Current TO 800 PM FRI	0.1" (90%) to 0.4" (60%) to 1.2" (15%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.