Flash Flood Prediction Program

-	Message 1's have been issued for the entire District and will be valid until 8:00 PM this evening.
-	An upper level disturbance will move overhead this afternoon and evening producing rain showers and thunderstorms. Thunderstorms will have the potential to produce brief heavy rainfall, hail and gusty winds. The first line or two of storms will likely be the strongest of the day with subsequent rounds into the evening likely favoring a general rain versus thunderstorms.
-	Prime time for thunderstorm activity will be from roughly 3pm through 7 or 8pm. After 7 or 8pm rain shower activity will continue into the evening but rainfall rates are anticipated to decrease becoming light to briefly moderate.

STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak thunderstorms will produce 0.1-0.4" of rain in 30-60 minutes. Moderate to strong thunderstorms will have the potential to produce rainfall rates of 0.4-1.0" in 10-30 minutes.

WORST CASE SCENARIO: Training of thunderstorm cells or a slower moving thunderstorm may result in up to 1.5" of rain in 60 minutes or less.

County	Message	Valid Times	Prime Time
Boulder County	1	200 PM TO 800 PM	300 PM TO 700 PM
Jefferson County	1	200 PM TO 800 PM	300 PM TO 700 PM
Broomfield County	1	200 PM TO 800 PM	300 PM TO 700 PM
Douglas County	1	200 PM TO 800 PM	300 PM TO 700 PM
Adams County	1	200 PM TO 800 PM	300 PM TO 700 PM
Denver County	1	200 PM TO 800 PM	300 PM TO 700 PM
DIA	1	200 PM TO 800 PM	300 PM TO 700 PM
Arapahoe County	1	200 PM TO 800 PM	300 PM TO 700 PM
the City of Aurora	1	200 PM TO 800 PM	300 PM TO 700 PM
Arvada	1	200 PM TO 800 PM	300 PM TO 700 PM
Wheat Ridge	1	200 PM TO 800 PM	300 PM TO 700 PM
Lakewood	1	200 PM TO 800 PM	300 PM TO 700 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 800 PM SAT	0.1" (80%) to 0.4" (40%) to 1.0" (20%)	ISSUED
Arapahoe	Current TO 800 PM SAT	0.1" (80%) to 0.4" (40%) to 1.0" (20%)	ISSUED
Boulder	Current TO 800 PM SAT	0.1" (80%) to 0.4" (40%) to 1.0" (15%)	ISSUED
Broomfield	Current TO 800 PM SAT	0.1" (80%) to 0.4" (40%) to 1.0" (15%)	ISSUED
Denver	Current TO 800 PM SAT	0.1" (80%) to 0.4" (40%) to 1.0" (20%)	ISSUED
Douglas	Current TO 800 PM SAT	0.1" (80%) to 0.4" (40%) to 1.0" (20%)	ISSUED
Jefferson	Current TO 800 PM SAT	0.1" (80%) to 0.4" (40%) to 1.0" (15%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 800 PM SAT	0.1" (90%) to 0.4" (40%) to 1.0" (10%)	ISSUED
Douglas	Current TO 800 PM SAT	0.1" (90%) to 0.4" (40%) to 1.0" (10%)	ISSUED
Jefferson	Current TO 800 PM SAT	0.1" (90%) to 0.4" (40%) to 1.0" (10%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.