Flash Flood Prediction Program

Message 1’s will continue to be valid as the threat of heavy rainfall continues.

Thunderstorms began forming along a boundary near the southern portions of the District earlier this afternoon, but dissipated before producing significant rainfall.

Dewpoints remain elevated in the low to mid 50s with temperatures climbing into the mid 80s. Currently, an outflow boundary is slowly approaching the District from the northeast, and has the potential to provide enough low level forcing to initiate thunderstorms into the evening.

STORM RAINFALL POTENTIAL AND DURATION: Typical showers/thunderstorms will produce a trace to 0.25” total in 10 to 30 minutes. A moderate thunderstorm will produce 0.25” to 0.50” total in 10 to 30 minutes. A strong thunderstorm will produce 0.50” to 0.75” total in 10 to 30 minutes.

WORST CASE SCENARIO: An anchored strong thunderstorm or training of thunderstorm cells has the potential to produce up to 1.50” in under 60 minutes.

County	Message	Valid Times	Prime Time
Lakewood	1	Current TO 900 PM	Current TO 830 PM
Wheat Ridge	1	Current TO 900 PM	Current TO 830 PM
Arvada	1	Current TO 900 PM	Current TO 830 PM
the City of Aurora	1	Current TO 900 PM	Current TO 830 PM
Arapahoe County	1	Current TO 900 PM	Current TO 830 PM
DIA	1	Current TO 900 PM	Current TO 830 PM
Denver County	1	Current TO 900 PM	Current TO 830 PM
Adams County	1	Current TO 900 PM	Current TO 830 PM
Douglas County	1	Current TO 900 PM	Current TO 830 PM
Broomfield County	1	Current TO 900 PM	Current TO 830 PM
Jefferson County	1	Current TO 900 PM	Current TO 830 PM
Boulder County	1	Current TO 900 PM	Current TO 830 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Arapahoe	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Boulder	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Broomfield	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Denver	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Douglas	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Jefferson	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Douglas	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED
Jefferson	Current TO 900 PM WED	0.25" (50%) to 0.5" (25%) to 0.75" (10%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.