Flash Flood Prediction Program

-	Message 1's have been issued for the entire District and be valid until 9:00 pm this evening.
-	With surface temperatures warming rapidly, thunderstorms are already beginning to develop over the higher terrain. Thunderstorms will become more numerous over the coming hours with 2-3 rounds of storms likely into the evening. The first 1-2 rounds will have the highest potential to produce heavy rainfall.
-	Although surface moisture has decreased significantly from yesterday evening, strong thunderstorms will still have the potential to produce heavy rainfall due to relatively slow storm motions. Most thunderstorms will move from W to E at 10-15mph. Strong thunderstorms may anchor or move more erratically.

STORM RAINFALL POTENTIAL AND DURATION: Typical weak to moderate thunderstorms will produce 0.1-0.3" of rain. Strong thunderstorms will have the potential to produce 0.3-0.8" of heavy rain in 10-30 minutes.

WORST CASE SCENARIO: A large, slow moving or stationary strong thunderstorm may produce up to 1.6" of rain in 45-60 minutes.

County	Message	Valid Times	Prime Time
Boulder County	1	Current TO 900 PM	1200 PM TO 800 PM
Jefferson County	1	Current TO 900 PM	1130 AM TO 800 PM
Broomfield County	1	Current TO 900 PM	1200 PM TO 800 PM
Douglas County	1	Current TO 900 PM	1200 PM TO 800 PM
Adams County	1	Current TO 900 PM	1200 PM TO 800 PM
Denver County	1	Current TO 900 PM	1200 PM TO 800 PM
DIA	1	Current TO 900 PM	1200 PM TO 800 PM
Arapahoe County	1	Current TO 900 PM	1200 PM TO 800 PM
the City of Aurora	1	Current TO 900 PM	1200 PM TO 800 PM
Arvada	1	Current TO 900 PM	1200 PM TO 800 PM
Wheat Ridge	1	Current TO 900 PM	1200 PM TO 800 PM
Lakewood	1	Current TO 900 PM	1200 PM TO 800 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 900 PM THU	0.1" (85%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Arapahoe	Current TO 900 PM THU	0.1" (85%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Boulder	Current TO 900 PM THU	0.1" (85%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Broomfield	Current TO 900 PM THU	0.1" (85%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Denver	Current TO 900 PM THU	0.1" (85%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Douglas	Current TO 900 PM THU	0.1" (85%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Jefferson	Current TO 900 PM THU	0.1" (85%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 900 PM THU	0.1" (90%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Douglas	Current TO 900 PM THU	0.1" (95%) to 0.4" (50%) to 0.8" (20%)	ISSUED
Jefferson	Current TO 900 PM THU	0.1" (95%) to 0.4" (50%) to 0.8" (20%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.