textproduct: Grand Junction

KEY MESSAGES

- Daily chances for showers and thunderstorms continues to highlight the forecast. - Heavy rainfall, lightning, small hail and outflow winds up to 40 mph will continue to be the primary risks of today's storms.

- Storms have the ability to produce flash flooding and debris flows in vulnerable terrain, including areas near and downstream of burn scars.

DISCUSSION

Issued at 1219 PM MDT Thu Jul 23 2026

TODAY:

Scattered to widespread showers and thunderstorms develop over the high country again today, with some storms moving over the valleys as the afternoon progresses. A mid-level cap is in place which will limit the strength of convection early this afternoon, but by mid afternoon storms will be capable of producing brief bouts of heavy rainfall. Localized flash flooding cannot be ruled out, especially in slot canyons, slick rock areas, recent burn scars, and other low- lying and flood- prone locations. Coverage and intensity of showers and storms will decrease after sunset, with mostly dry conditions expected after midnight.

TOMORROW:

A "drier" airmass moves into eastern Utah and and western Colorado tomorrow with high pressure building in overhead. However, PWATs of 125-150% will continue to support terrain- based showers and storms during peak heating. This drier, more stable airmass will help suppress flash flooding concerns for the most part. High pressure will also support seasonable to slightly above normal temperatures, with a gradual warming trend expected into the weekend.

LOOKING AHEAD:

A plume of monsoonal mositure is setting up over the Great Basin. Mositure will gradually increase throughout the weekend, especially along and north of I-70, as it wraps around the surface high. As a result, daily showers an storms are expected through the weekend and well into the coming week.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 508 PM MDT Thu Jul 23 2026

Thunderstorm activity is gradually diminishing at most terminals this evening. The overnight period will see generally light winds with terrain driven tendencies. Skies will generally clear out after this push of cloud cover moves eastward. Mid level clouds will begin to develop again by Friday afternoon. There is a chance for afternoon thunderstorms Friday mostly confined to the high country terminals. Included PROB30 groups to account for that. All that being said, VFR conditions will prevail.

HYDROLOGY

Issued at 1222 AM MDT Thu Jul 23 2026

Scattered thunderstorms capable of producing heavy rain are expected to develop Thursday afternoon. Rainfall rates of 1-2 inches per hour will be possible with the stronger storms. These rates could lead to flash flooding and debris flows, especially over steep terrain and recent burn scars. Also, rain over the past several days has lead to saturated soils, which increase the chances for excessive runoff.

As a reminder: Keep an eye on our forecasts through the end of the week and stay tuned for updated hydrology alerts if visiting or if you reside below terrain vulnerable to flash flooding and/or debris flows. Dry creeks and arroyos can fill quickly and without warning from storms miles away.

GJT WATCHES/WARNINGS/ADVISORIES

CO...None. UT...None.