Flash Flood Prediction Program

-	Message 1's have been issued for the entire District and will be valid until 8:00pm this evening.
-	Modest surface moisture in tandem with a passing upper level disturbance will result in a round of thunderstorms this afternoon. Relatively fast storm motions from W to E at around 20mph will keep the potential for heavy rainfall short lived most areas. Training of thunderstorm cells or a large, slower moving strong thunderstorm will have the potential to produce an extended period of heavy rain that may lead to excessive runoff.
-	Strong thunderstorms that develop today may also become severe with gusty winds in excess of 50mph, large hail of 1" or more in diameter being the primary threats. Generally one round of thunderstorms is expected but some areas could see a couple rounds of thunderstorm activity.

STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms will have the potential to produce 0.3-0.9" in 10-30 minutes.

WORST CASE SCENARIO: A large, slower moving thunderstorm or training of thunderstorm cells will have the potential to produce up to 1.6" of rain in 45-60 minutes.

County	Message	Valid Times	Prime Time
Boulder County	1	1200 PM TO 800 PM	130 PM TO 700 PM
Jefferson County	1	1200 PM TO 800 PM	130 PM TO 700 PM
Broomfield County	1	1200 PM TO 800 PM	130 PM TO 700 PM
Douglas County	1	1200 PM TO 800 PM	130 PM TO 700 PM
Adams County	1	1200 PM TO 800 PM	130 PM TO 700 PM
Denver County	1	1200 PM TO 800 PM	130 PM TO 700 PM
DIA	1	1200 PM TO 800 PM	130 PM TO 700 PM
Arapahoe County	1	1200 PM TO 800 PM	130 PM TO 700 PM
the City of Aurora	1	1200 PM TO 800 PM	130 PM TO 700 PM
Arvada	1	1200 PM TO 800 PM	130 PM TO 700 PM
Wheat Ridge	1	1200 PM TO 800 PM	130 PM TO 700 PM
Lakewood	1	1200 PM TO 800 PM	130 PM TO 700 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	1230 PM TO 800 PM	0.1" (90%) to 0.3" (60%) to 0.9" (30%)	ISSUED
Arapahoe	1230 PM TO 800 PM	0.1" (90%) to 0.3" (60%) to 0.9" (30%)	ISSUED
Boulder	1230 PM TO 800 PM	0.1" (90%) to 0.3" (50%) to 0.9" (25%)	ISSUED
Broomfield	1230 PM TO 800 PM	0.1" (90%) to 0.3" (50%) to 0.9" (25%)	ISSUED
Denver	1230 PM TO 800 PM	0.1" (90%) to 0.3" (50%) to 0.9" (30%)	ISSUED
Douglas	1230 PM TO 800 PM	0.1" (90%) to 0.3" (50%) to 0.9" (25%)	ISSUED
Jefferson	1230 PM TO 800 PM	0.1" (90%) to 0.3" (50%) to 0.9" (25%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 800 PM SAT	0.1" (95%) to 0.3" (50%) to 0.9" (20%)	ISSUED
Douglas	Current TO 800 PM SAT	0.1" (95%) to 0.3" (50%) to 0.9" (20%)	ISSUED
Jefferson	Current TO 800 PM SAT	0.1" (95%) to 0.3" (50%) to 0.9" (20%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.