Flash Flood Prediction Program

-	Slow moving to nearly stationary thunderstorms over the foothills of Jefferson County may push a rain cooled outflow boundary eastward onto the plains shortly. This rain cooled outflow boundary/gust front may be able to overcome a warm layer of air aloft and generate new storm development over the plains in the coming hours.
-	Thunderstorms if they develop will be slow moving and capable of producing moderate to heavy rainfall for extended periods of time. There is no indication that storms are imminent but may develop over the coming hours if conditions come together just right.
-	Best chances for thunderstorm activity continues to be over the foothills through about 8pm this evening.

STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms will produce 0.3-0.9" in 10-30 minutes. Strong thunderstorms will have the potential to produce 0.5-1.5" in 10-30 minutes.

WORST CASE SCENARIO: A stationary moderate to strong thunderstorm may result in up to 2.5" of rain in 60-90 minutes.

A LOOK AHEAD: We will tack on a few more degrees to high temperatures on Wednesday and add a little more moisture. With more heat and moisture to work with there will be a better chance for afternoon thunderstorms, some of which may contain heavy rainfall. Thursday and Friday will feature a high likelihood of afternoon and evening thunderstorms with the potential to produce heavy rainfall that may result in excessive runoff and flash flooding.

Location	Prime Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	400 PM TO 800 PM	0.1" (60%) to 0.3" (30%) to 0.9" (15%)	MOD
Arapahoe	400 PM TO 800 PM	0.1" (60%) to 0.3" (30%) to 0.9" (15%)	MOD
Boulder	400 PM TO 800 PM	0.1" (65%) to 0.3" (40%) to 0.9" (20%)	MOD
Broomfield	400 PM TO 800 PM	0.1" (60%) to 0.3" (30%) to 0.9" (15%)	MOD
Denver	400 PM TO 800 PM	0.1" (60%) to 0.3" (30%) to 0.9" (15%)	MOD
Douglas	400 PM TO 800 PM	0.1" (65%) to 0.3" (40%) to 0.9" (20%)	MOD
Jefferson	400 PM TO 800 PM	0.1" (65%) to 0.3" (40%) to 0.9" (20%)	MOD
Foothills above 6500ft
Boulder	Current TO 800 PM TUE	0.1" (95%) to 0.3" (70%) to 0.9" (30%)	MOD
Douglas	Current TO 800 PM TUE	0.1" (95%) to 0.3" (70%) to 0.9" (30%)	MOD
Jefferson	Current TO 800 PM TUE	0.1" (95%) to 0.3" (70%) to 0.9" (30%)	MOD

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.