Flash Flood Prediction Program

-	Message 1's have been issued for portions of the District along and S of I-70 including Arapahoe, Denver, Douglas and Jefferson Counties and will be valid until 8:00pm.
-	A strong thunderstorm has developed over Jefferson County and is expected to move eastward through the District with the potential for heavy rainfall that may lead to excessive runoff. Upper level steering winds will move storms from W to E at around 15-20mph.
-	Storms are expected to move from W to E and generally remain along and S of I-70 with weaker storms northward.

STORM RAINFALL POTENTIAL AND DURATION: Moderate to strong thunderstorms will have the potential to produce 0.4-1.0" of heavy rain in 10-30 minutes.

WORST CASE SCENARIO: Thunderstorms anchoring to the foothills or slower moving thunderstorms may result in up to 1.6" in 45-60 minutes.

County	Message	Valid Times	Prime Time
Jefferson County	1	Current TO 800 PM	Current TO 700 PM
Douglas County	1	Current TO 800 PM	Current TO 700 PM
Denver County	1	Current TO 800 PM	Current TO 700 PM
Arapahoe County	1	Current TO 800 PM	Current TO 700 PM
the City of Aurora	1	Current TO 800 PM	Current TO 700 PM
Arvada	1	Current TO 800 PM	Current TO 700 PM
Wheat Ridge	1	Current TO 800 PM	Current TO 700 PM
Lakewood	1	Current TO 800 PM	Current 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" (50%) to 0.4" (20%) to 1.0" (10%)	MOD
Arapahoe	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (30%)	ISSUED
Boulder	Current TO 800 PM TUE	0.1" (60%) to 0.4" (30%) to 1.0" (10%)	MOD
Broomfield	Current TO 800 PM TUE	0.1" (60%) to 0.4" (30%) to 1.0" (10%)	MOD
Denver	Current TO 800 PM TUE	0.1" (90%) to 0.4" (60%) to 1.0" (30%)	ISSUED
Douglas	Current TO 800 PM TUE	0.1" (95%) to 0.4" (65%) to 1.0" (30%)	ISSUED
Jefferson	Current TO 800 PM TUE	0.1" (95%) to 0.4" (65%) to 1.0" (30%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 800 PM TUE	0.1" (60%) to 0.4" (30%) to 1.0" (10%)	MOD
Douglas	Current TO 800 PM TUE	0.1" (100%) to 0.4" (75%) to 1.0" (40%)	ISSUED
Jefferson	Current TO 800 PM TUE	0.1" (100%) to 0.4" (75%) to 1.0" (40%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.