Flash Flood Prediction Program

A round of storms initiated along the foothills this afternoon bringing some moderate to brief heavy rainfall with 0.30”-0.75” total in 10-30 minutes for areas just west of the District. These storms produced a strong gust front that moved eastwardly through the District with gusts up to 35mph. This gust front pushed through the District and resulted in a strong line of storms east of the District. This line of storms will not move very much as storms pulse up along the gust. This line of storms could potentially produce an additional gust front which could move west and back into the District. This will result in a slight chance for storms to develop within the District, favoring eastern portions of the District at this time. This potential will keep Message 1’s valid until the evening as the threat of moderate to heavy rainfall remains. Storm intensities will decrease after sundown with a few off and on showers possible through midnight.

STORM RAINFALL POTENTIAL AND DURATION: Typical showers and thunderstorms will produce 0.05”-0.30” total in 10-30 minutes. A moderate to strong shower/thunderstorm will produce 0.30”-0.80” total in 10-30 minutes.

WORST CASE SCENARIO: A strong stationary thunderstorm or training of thunderstorm cells will have the potential to produce 1.20” total in 30-60 minutes.

County	Message	Valid Times	Prime Time
Lakewood	1	Current TO 1000 PM	Current TO 930 PM
Wheat Ridge	1	Current TO 1000 PM	Current TO 930 PM
Arvada	1	Current TO 1000 PM	Current TO 930 PM
the City of Aurora	1	Current TO 1000 PM	Current TO 930 PM
Arapahoe County	1	Current TO 1000 PM	Current TO 930 PM
DIA	1	Current TO 1000 PM	Current TO 930 PM
Denver County	1	Current TO 1000 PM	Current TO 930 PM
Adams County	1	Current TO 1000 PM	Current TO 930 PM
Douglas County	1	Current TO 1000 PM	Current TO 930 PM
Broomfield County	1	Current TO 1000 PM	Current TO 930 PM
Jefferson County	1	Current TO 1000 PM	Current TO 930 PM
Boulder County	1	Current TO 1000 PM	Current TO 930 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Arapahoe	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Boulder	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Broomfield	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Denver	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Douglas	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Jefferson	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Douglas	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED
Jefferson	Current TO 1159 PM FRI	0.05" (40%) to 0.3" (20%) to 0.8" (5%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.