textproduct: Pueblo

KEY MESSAGES

- Active monsoon plume and embedded disturbances will keep scattered to numerous showers and thunderstorms across the mountains into tonight.

- Flash Flood Watch for the Willow Burn Scar and the Chalk Cliffs has been issue for this afternoon and evening

- A drying and warming trend returns for Tuesday through Thursday.

- Thunderstorm chances increase again late week into next weekend, especially over the mountains.

SHORT TERM /THROUGH TONIGHT/

Issued at 1238 AM MDT Mon Aug 31 2026

An active monsoon plume remains over the area within a broad swath of 100-150 percent of normal precipitable waters extending from the Desert Southwest across the 4 Corners region and across central and northeast CO. Scattered showers with isolated embedded thunderstorms will gradually decrease overnight across southern CO, with some spotty light to moderate rainfall and lightning the primary risks through 3 AM.

A more potent disturbance is progged to move across CO later today through this evening triggering another round of showers and thunderstorms across the mountains and adjacent plains. With precipitable waters running around 120-160% of normal, concerns will be high for heavy rainfall capable of producing flash flooding, particularly along the Continental Divide where the moisture will be greatest and the signal is strongest for greater than 0.5 inches of rainfall in an hour. Based on conceptual models and DESI probabilities, hoisted a Flash Flood Watch for the Willow Burn Scar and the Chalk Cliffs for today. There are still some uncertainties with this scenario, as persistent clouds could keep conditions more stable, and hinder or delay the stronger convective development needed for heavier rainfall rates. Another concern is that activity may persist well into the evening, and perhaps as late as 10-11 PM according to some of the CAMS as forcing from the disturbance moves across. Will run the Flash Flood Watch from noon until midnight for now as conceptual models suggest the risk for flash flooding is sufficient.

Conditions do not look as favorable for heavy rainfall on the Aspen Acres burn scar with probabilities of seeing 0.25 inches of rainfall around 0 percent in the HREF and NBM. Have opted not to include the Aspen Acres burn scar in a Flash Flood Watch given greater uncertainty. But if later runs start to show a signal for heavier rainfall, expansions of the Flash Flood Watch to include Aspen Acres may become necessary. As storms push off into the southeast plains the will encounter greater CAPE and shear, with mean CAPE up to 1500 J/kg off HREF, and deep layer shears running around 35-40 kts. One or two strong storms will be possible east of a line from Rocky Ford to Trinidad. Some small hail up an inch, heavy rainfall, and wind gusts up to 55 mph will be possible with the stronger storms. Storms will last well into the evening and even into overnight hours until the shortwave passes off to the north after 06z.

Otherwise, it will be another relatively cool day given more convective cloudiness and thunderstorm outflows in the late afternoon and evening. Didn't stray far from NBM.

LONG TERM /TUESDAY THROUGH SUNDAY/

Issued at 1238 AM MDT Mon Aug 31 2026

The weather dries out and warms up Tuesday through Thursday across southern Colorado. There will still be sufficient moisture in southwest flow to support some isolated to scattered thunderstorms on Tuesday, but these will be very hit or miss which should limit the risk for flash flooding on burn scars. Wednesday and Thursday look even drier with temperatures on the far east plains pushing into the upper 90s for highs by Thursday.

Southerly flow around the southern U.S upper ridge sends another round of moisture northward into southern CO for Friday with precipitable waters increasing to between 100-130% of normal. This should bring a slight up tick in thunderstorm chances across the area by Friday, especially for the mountains. Precipitable waters continue to increase through next weekend bringing a better chance for heavy rains and flash flooding, particularly along the Continental Divide. Meanwhile, deep southwest flow aloft limits the persistence of low level moisture along the lower east facing slopes with dew points dropping into the 40s in the afternoon. This should reduce but not completely eliminate the flash flood risk on the Aspen Acres burn scar. Any storms that push off into the adjacent plains could produce gusty outflow winds up to 50 mph and lightning, along with some brief moderate to heavy rainfall. -KT

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1020 PM MDT Sun Aug 30 2026

Scattered elevated showers/storms have persisted this evening and should continue over the next few hours posing some risk of gusty winds near terminals. Best confidence in impact will be at KCOS where elevated showers/storms are still noted moving in from the southwest. A break in convection should come for much of the early and mid morning hours before another swath of monsoonal moisture surges into southern CO, returning chances for scattered convection Monday afternoon and evening. Kept mention of convection as PROB30s for KCOS and KPUB.

PUB WATCHES/WARNINGS/ADVISORIES

Flash Flood Watch from noon MDT today through this evening for COZ059>061.