Flash Flood Prediction Program

Messages have been issued for the entire District, effective until 10:00 PM.

Storms have started to initiate along the foothills and are expected to start moving into the District over the next hour. Slow moving, gust-front driven storms are expected to propagate from west to east around 15-20 mph. However, gust fronts will likely result in additional, slower-moving thunderstorms which will have the potential for moderate to heavy rainfall.

Heavy Rainfall is most likely to occur until 9:00 PM tonight. A few lingering showers may persist after 9pm, but with elevated moisture in place, any lingering showers will be efficient rainfall producers. Once showers dissipate, skies will clear through the overnight with temperatures dropping into the 60s.

STORM RAINFALL POTENTIAL AND DURATION: Thunderstorms will have the potential to produce rainfall rates of 0.25”-0.75” in 10-30 minutes.

A slow-moving thunderstorm or a large thunderstorm complex may result in up to 1.50” of rain in 45-60 minutes.

WORST CASE SCENARIO: A slow-moving thunderstorm or a large thunderstorm complex may result in up to 1.50” of rain in 45-60 minutes.

County	Message	Valid Times	Prime Time
Boulder County	1	Current TO 1000 PM	Current TO 900 PM
Jefferson County	1	Current TO 1000 PM	Current TO 900 PM
Broomfield County	1	Current TO 1000 PM	Current TO 900 PM
Douglas 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
DIA	1	Current TO 1000 PM	Current TO 900 PM
Arapahoe 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	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Arapahoe	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Boulder	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Broomfield	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Denver	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Douglas	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Jefferson	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Douglas	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED
Jefferson	Current TO 1000 PM TUE	0.25" (55%) to 0.5" (35%) to 0.75" (15%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.