Flash Flood Prediction Program

Message 1’s will be allowed to expire at 10pm as the threat of heavy rainfall has ended for the day.

A few showers persist over the District at this time, however, the threat of heavy rainfall has come to an end. These showers and a weak thunderstorm or two will last for the next few hours favoring areas W of I-25 over the foothills, before gradually clearing into the overnight. Storm motions continue to be south to north, with areas along the foothills and west of I25 having the best chance for rain showers through the rest of the evening.

Not much change in the overall pattern heading into tomorrow with another good chance for widespread afternoon/eve rain showers and thunderstorms. There will continue to be a chance of severe weather under stronger storms, mainly for gusty winds and hail up to an inch. These strong thunderstorms will likely contain pockets of heavy rainfall which could lead to isolated flash flooding.

STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers will produce a TR-0.2” in 10-30 minutes. A moderate rain shower, or a weak thunderstorm could produce 0.2-0.4” in 10-30 minutes.

WORST CASE SCENARIO: A moderate to strong thunderstorm has the potential to produce 0.4-0.8” in up to 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 1159 PM WED	Trace (50%) to 0.2" (20%) to 0.4" (10%)	NONE
Arapahoe	Current TO 1159 PM WED	Trace (50%) to 0.2" (20%) to 0.4" (10%)	NONE
Boulder	Current TO 1159 PM WED	Trace (85%) to 0.2" (40%) to 0.4" (10%)	NONE
Broomfield	Current TO 1159 PM WED	Trace (65%) to 0.2" (30%) to 0.4" (10%)	NONE
Denver	Current TO 1159 PM WED	Trace (50%) to 0.2" (20%) to 0.4" (10%)	NONE
Douglas	Current TO 1159 PM WED	Trace (50%) to 0.2" (20%) to 0.4" (10%)	NONE
Jefferson	Current TO 1159 PM WED	Trace (80%) to 0.2" (40%) to 0.4" (10%)	NONE
Foothills above 6500ft
Boulder	Current TO 1159 PM WED	Trace (95%) to 0.2" (60%) to 0.4" (20%)	NONE
Douglas	Current TO 1159 PM WED	Trace (95%) to 0.2" (60%) to 0.4" (20%)	NONE
Jefferson	Current TO 1159 PM WED	Trace (95%) to 0.2" (60%) to 0.4" (20%)	NONE

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.