Flash Flood Prediction Program

-	A weak ridge of high pressures remains over the Central Rockies on Saturday, as a cold front approaches Colorado from the NE. Daytime temperatures will be slightly cooler today, topping out in the low to mid 70s by afternoon.
-	Surface moisture will be on the increase later this morning and afternoon, as moist easterly flow arrives behind the front. The result will be an increased chance for showers and thunderstorms capable of heavy rainfall.
-	Showers and thunderstorms will fire early this afternoon, with 1-2 waves of storms tracking ENE across the plains at around 20-25mph. The best chance for a storm over the District will occur between about 1pm-6pm, with only isolated chances for additional storms persisting into the evening hours.

STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate showers and thunderstorms will produce rainfall amounts of 0.05-0.25" in 10-30 minutes. Stronger thunderstorms may produce rainfall between 0.25-0.70" in 10-30 minutes.

WORST CASE SCENARIO: A strong to severe thunderstorm produces rainfall up to 1.7" in 30-60 minutes.

A LOOK AHEAD: Moisture increases further on Sunday, as a trough of low pressure over S. California draws subtropical moisture N along the Front Range. Afternoon temperatures will rebound to around 80, with continued elevated chances for thunderstorms capable of heavy rainfall.

Location	Prime Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	100 PM TO 600 PM	0.1" (80%) to 0.3" (60%) to 0.7" (20%)	MOD
Arapahoe	100 PM TO 600 PM	0.1" (90%) to 0.3" (65%) to 0.7" (25%)	MOD
Boulder	100 PM TO 600 PM	0.1" (70%) to 0.3" (40%) to 0.7" (10%)	LOW
Broomfield	100 PM TO 600 PM	0.1" (80%) to 0.3" (50%) to 0.7" (10%)	LOW
Denver	100 PM TO 600 PM	0.1" (80%) to 0.3" (60%) to 0.7" (20%)	MOD
Douglas	100 PM TO 600 PM	0.1" (90%) to 0.3" (65%) to 0.7" (25%)	MOD
Jefferson	100 PM TO 600 PM	0.1" (80%) to 0.3" (50%) to 0.7" (10%)	LOW
Foothills above 6500ft
Boulder	1200 PM TO 600 PM	0.1" (70%) to 0.3" (40%) to 0.7" (10%)	LOW
Douglas	1200 PM TO 600 PM	0.1" (85%) to 0.3" (55%) to 0.7" (10%)	LOW
Jefferson	1200 PM TO 600 PM	0.1" (85%) to 0.3" (55%) to 0.7" (10%)	LOW

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.