Flash Flood Prediction Program

A wave of unsettled weather will continue traversing the Northern Plains today, transporting a broad envelope of Pacific mid-level moisture into Colorado. Coupled with favorable upper-level support, another cool and stormy day is expected. The stratus deck blanketing Northeastern Colorado this morning will remain in place throughout the day, encouraging cooler temperatures in the 70s.

Dewpoints will be in the upper 50s to low 60s, and precipitable water (PWAT) values around 1.00”. The right entrance region of the upper-level jet will be over northeast Colorado broadly today, providing sufficient lift for convection initiation. Isolated thunderstorms are expected to develop by the early afternoon over complex terrain, becoming scattered to widespread as outflows propagate convection onto the plains. Storm motions will be from west to east around 25mph. Quick storm motions will help limit point rainfall amounts, but stronger storms will be capable of producing efficient, moderate to briefly heavy rainfall.

STORM RAINFALL POTENTIAL AND DURATION: Typical showers and thunderstorms today have the potential to produce between a 0.25-0.50” in 10-30 minutes. Stronger showers and thunderstorms today have the potential to produce between a 0.50-0.75” in 10-30 minutes.

WORST CASE SCENARIO: A slow-moving stronger thunderstorm may be capable of producing 1.50” or more in 30 minutes or less.

A LOOK AHEAD: Starting tomorrow, cloud cover should start to break up with some drying aloft. Temperatures will be in the 80s with chances for afternoon showers and thunderstorms.

Location	Prime Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Arapahoe	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Boulder	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Broomfield	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Denver	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Douglas	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Jefferson	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Foothills above 6500ft
Boulder	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Douglas	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD
Jefferson	1200 PM TO 1000 PM	0.25" (75%) to 0.5" (50%) to 0.75" (25%)	MOD

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.