Flash Flood Prediction Program

As the remnants of a tropical system continue to shift east into the District, showers and thunderstorms along the Front Range Urban Corridor are expected today and tonight. Isolated to scattered storm activity is expected across the District today as afternoon temperatures reach the upper 70s to low 80s, dew points in the low to mid 50s, and precipitable water (PWAT) values between 0.85” to 1.00”. Storms are expected to move southeast around 25-30 mph. Quick storm motions will help limit point rainfall amounts. Thunderstorms are expected to continue this evening, then move east overnight.

STORM RAINFALL POTENTIAL AND DURATION: Typical showers will produce rainfall of TR-0.25” total in 10-30 minutes. Stronger storms have the potential to produce heavy rainfall of 0.25” to 0.75” total in 10-30 minutes.

WORST CASE SCENARIO: Training or anchored thunderstorms have the potential to produce 0.75” to 1.25” total in 30-60 minutes.

A LOOK AHEAD: Upper-level winds will shift tomorrow, transporting much dryer and warmer conditions into the state. Tomorrow will be sunny with afternoon temperatures warming into the low to mid 80s. Thunderstorm activity will be broadly limited to complex terrain. The remainder of the week is expected to be dry and hot, with afternoon temperatures climbing into the 90s under sunny skies.

Location	Prime Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Arapahoe	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Boulder	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Broomfield	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Denver	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Douglas	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Jefferson	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Foothills above 6500ft
Boulder	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Douglas	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Jefferson	200 PM TO 900 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.