Flash Flood Prediction Program

-	Message 1's have been issued for the entire District and will be valid until 8:00pm this evening.
-	An upper level trough of low pressure will move through the District this afternoon likely initiating 1-2 rounds of showers and thunderstorms. Thunderstorms are beginning to develop over the higher terrain currently and will be moving onto the plains between 2-3pm. Thunderstorms are expected to form N to S oriented lines which will move from W to E through the District rather quickly. The fast storm motions will help to limit point rainfall amounts from a single storm helping to keep any heavy rainfall relatively brief.
-	The first round of storms will have the greatest potential to produce heavy rainfall with any subsequent rounds favoring light to brief moderate rain. Greatest threat for extended periods of heavy rainfall will be from training of thunderstorm cells or slower moving large thunderstorms.

STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms will produce 0.1-0.4" in 10-30 minutes. Strong thunderstorms will have the potential to produce 0.4-1.0" of heavy rain in 10-30minutes. Supplemental QPF is available at https://qpf.udfcd.org

WORST CASE SCENARIO: A very large or slower moving thunderstorm may produce up to 1.6" of rain in 45-60 minutes.

County	Message	Valid Times	Prime Time
Arvada	1	Current TO 800 PM	200 PM TO 700 PM
the City of Aurora	1	Current TO 800 PM	200 PM TO 700 PM
Arapahoe County	1	Current TO 800 PM	200 PM TO 700 PM
DIA	1	Current TO 800 PM	200 PM TO 700 PM
Denver County	1	Current TO 800 PM	200 PM TO 700 PM
Adams County	1	Current TO 800 PM	200 PM TO 700 PM
Douglas County	1	Current TO 800 PM	200 PM TO 700 PM
Broomfield County	1	Current TO 800 PM	200 PM TO 700 PM
Jefferson County	1	Current TO 800 PM	200 PM TO 700 PM
Boulder County	1	Current TO 800 PM	200 PM TO 700 PM
Wheat Ridge	1	Current TO 800 PM	200 PM TO 700 PM
Lakewood	1	Current TO 800 PM	200 PM TO 700 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Arapahoe	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Boulder	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Broomfield	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Denver	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Douglas	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Jefferson	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Douglas	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED
Jefferson	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (20%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.