Flash Flood Prediction Program

-	Message 1's have been issued for the entire District until 11:00pm.
-	Thunderstorms are developing over the foothills at this time. With deep moisture in place along with slow storm motions with these initial storms, there is potential for heavy rainfall over the higher elevations of the District in the next 1-2 hours. Initial thunderstorms will likely weaken as they move onto the lower elevations early this afternoon due to a capping inversion in place. However, this cap will erode by mid to late afternoon as cooler air aloft arrives with an approaching disturbance.
-	Storms will have the potential to become strong to severe on the plains this afternoon, with heavy rainfall and excessive runoff possible. Storms could also produce large hail, gusty straight-line winds, and frequent lightning. Thunderstorm activity could linger well into the evening before tapering off late tonight.

STORM RAINFALL POTENTIAL AND DURATION: Thunderstorms will be capable of producing rainfall of 0.5-1.5" in 10-30 minutes.

WORST CASE SCENARIO: A slow-moving thunderstorm or training of thunderstorm cells results in heavy rainfall of up to 3.0" in 90-120 minutes.

County	Message	Valid Times	Prime Time
Douglas County	1	Current TO 1100 PM	300 PM TO 900 PM
Broomfield County	1	Current TO 1100 PM	300 PM TO 900 PM
Jefferson County	1	Current TO 1100 PM	300 PM TO 900 PM
Boulder County	1	Current TO 1100 PM	300 PM TO 900 PM
Adams County	1	Current TO 1100 PM	300 PM TO 900 PM
Denver County	1	Current TO 1100 PM	300 PM TO 900 PM
DIA	1	Current TO 1100 PM	300 PM TO 900 PM
Arapahoe County	1	Current TO 1100 PM	300 PM TO 900 PM
the City of Aurora	1	Current TO 1100 PM	300 PM TO 900 PM
Arvada	1	Current TO 1100 PM	300 PM TO 900 PM
Wheat Ridge	1	Current TO 1100 PM	300 PM TO 900 PM
Lakewood	1	Current TO 1100 PM	300 PM TO 900 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 1100 PM MON	0.1" (95%) to 0.5" (60%) to 1.5" (30%)	ISSUED
Arapahoe	Current TO 1100 PM MON	0.1" (95%) to 0.5" (60%) to 1.5" (30%)	ISSUED
Boulder	Current TO 1100 PM MON	0.1" (95%) to 0.5" (50%) to 1.5" (20%)	ISSUED
Broomfield	Current TO 1100 PM MON	0.1" (95%) to 0.5" (50%) to 1.5" (20%)	ISSUED
Denver	Current TO 1100 PM MON	0.1" (95%) to 0.5" (50%) to 1.5" (20%)	ISSUED
Douglas	Current TO 1100 PM MON	0.1" (95%) to 0.5" (60%) to 1.5" (30%)	ISSUED
Jefferson	Current TO 1100 PM MON	0.1" (95%) to 0.5" (50%) to 1.5" (20%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 1100 PM MON	0.1" (95%) to 0.5" (55%) to 1.5" (25%)	ISSUED
Douglas	Current TO 1100 PM MON	0.1" (95%) to 0.5" (55%) to 1.5" (25%)	ISSUED
Jefferson	Current TO 1100 PM MON	0.1" (95%) to 0.5" (55%) to 1.5" (25%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.