Flash Flood Prediction Program

Message 1's have been issued for the entire District effective until 10pm this evening.

A gust front from the NE has moved through the District and initiated thunderstorms along the foothills. These storms have moved off of the foothills at this time and will move through the District over the next couple of hours, resulting in a chances for some isolated heavy rainfall. Storm motions will be from the NW to SE between 10-15mph as these storms move out onto the eastern plains, which should help limit point rainfall amounts. However, storms formed off and along outflow boundaries will have the best chance for longer lasting heavy rainfall.

The biggest threat for storms will be from now through 9pm. Rain showers and thunderstorms should start to taper off after this round of activity rolls through, with skies gradually clearing after 10pm.

STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers/isolated thunderstorms will produce 0.1-0.3" in 10-30 minutes. A Moderate to strong thunderstorm will produce 0.3-0.8" in 10-30
minutes.

WORST CASE SCENARIO: A slow moving/stationary thunderstorm formed off an outflow boundary,
or training of thunderstorm cells has the potential to produce up to 1.6" in under 60 minutes.

County	Message	Valid Times	Prime Time
DIA	1	Current TO 1000 PM	Current TO 900 PM
Arapahoe County	1	Current TO 1000 PM	Current TO 900 PM
Adams County	1	Current TO 1000 PM	Current TO 900 PM
Denver County	1	Current TO 1000 PM	Current TO 900 PM
Douglas County	1	Current TO 1000 PM	Current TO 900 PM
Broomfield County	1	Current TO 1000 PM	Current TO 900 PM
Boulder County	1	Current TO 1000 PM	Current TO 900 PM
Jefferson County	1	Current TO 1000 PM	Current TO 900 PM
the City of Aurora	1	Current TO 1000 PM	Current TO 900 PM
Arvada	1	Current TO 1000 PM	Current TO 900 PM
Wheat Ridge	1	Current TO 1000 PM	Current TO 900 PM
Lakewood	1	Current TO 1000 PM	Current TO 900 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 1000 PM TUE	0.1" (80%) to 0.3" (50%) to 0.8" (20%)	ISSUED
Arapahoe	Current TO 1000 PM TUE	0.1" (80%) to 0.3" (50%) to 0.8" (20%)	ISSUED
Boulder	Current TO 1000 PM TUE	0.1" (80%) to 0.3" (50%) to 0.8" (20%)	ISSUED
Broomfield	Current TO 1000 PM TUE	0.1" (80%) to 0.3" (50%) to 0.8" (20%)	ISSUED
Denver	Current TO 1000 PM TUE	0.1" (80%) to 0.3" (50%) to 0.8" (20%)	ISSUED
Douglas	Current TO 1000 PM TUE	0.1" (80%) to 0.3" (50%) to 0.8" (20%)	ISSUED
Jefferson	Current TO 1000 PM TUE	0.1" (80%) to 0.3" (50%) to 0.8" (20%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 1000 PM TUE	0.1" (50%) to 0.3" (30%) to 0.8" (5%)	ISSUED
Douglas	Current TO 1000 PM TUE	0.1" (50%) to 0.3" (30%) to 0.8" (5%)	ISSUED
Jefferson	Current TO 1000 PM TUE	0.1" (50%) to 0.3" (30%) to 0.8" (5%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.