textproduct: Grand Junction

KEY MESSAGES

- Showers and thunderstorms will continue on Thursday afternoon,with lighter coverage across the region. - Heavy rainfall, lightning, small hail and outflow winds 40-50 mph will continue to threaten.

- 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 1046 PM MDT Wed Jul 22 2026

A developing omega block will keep high pressure locked in place for the foreseeable future. The shortwave trough that pushed through this evening will introduce some cooler air that should knock afternoon highs back down just below normal on Thursday. Unfortunately, that high pressure exerts itself yet again on Friday and beyond to push afternoon highs up into the triple digits for our lower elevation valleys. Monsoonal moisture will dial back too, taking some of the flooding risks with it. Afternoon showers and thunderstorms will also lose some of their dynamic support. This will reduce widespread hydrological concerns. However, isolated cases of heavy rain will still pose a flood risk near saturated soils and sensitive burn scars.

This weekend high pressure arcs across the Rockies and the Great Plains. Weak monsoonal moisture will continue to trickle in, but widespread upticks are not expected until perhaps early next week. Temperatures will trend 5 to 10 degrees above normal for much of the region. Afternoon showers on the terrain will offer some relief to the mountains and a few valleys. Models begin to hint at a better plume of moisture on Monday. This could increase storm coverage, but it's still a little premature to get committed. A tropical feature working along the west coast of Mexico could send some better moisture up our way mid week.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 517 AM MDT Thu Jul 23 2026

Limited shower activity is lifting across the north early this morning with minimal impact and VFR conditions are in place across the board. Lingering moisture will lead to another round of shower and thunderstorm activity as heating picks up by mid day. Most TAF sites again have PROB30 groups to cover this with gusty winds the main threat...though there is a low probability of MVFR if a stronger shower were to move over the airfield.

HYDROLOGY

Issued at 1046 PM MDT Wed Jul 22 2026

Monsoonal moisture will thin some Thursday. Scattered thunderstorms capable of producing heavy rain are expected to continue 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.