textproduct: Grand Junction

KEY MESSAGES

- More storms on tap Wednesday afternoon and evening with an uptick in activity and coverage expected.

- Localized flash flooding will be possible especially over burn scars and steep terrain. Gusty winds, lightning, and small hail will also be possible.

- Hot and predominately dry conditions move in for the weekend and beyond.

DISCUSSION

Issued at 916 PM MDT Tue Jul 28 2026

There is a change on the horizon but not until we get at least one more day of active and widespread convection. The difference today will be a shortwave trough that will move through and bring increased lift across the area. Everything else remains in place...the moisture, the instability, all the things. As the wave moves through, convection will become more scattered to widespread. As previously mentioned, storm motions should be somewhat faster than seen recently. Despite that, localized flash flooding is possible, especially over vulnerable terrain and burn scars. Small hail, gusty winds, and lightning remain a concern as well.

Behind the aformentioned shortwave, dry air beings to filter back into the region. It will take a few days before residual moisture is completely scrubbed from the atmosphere so we can expect some convection Thursday and Friday with coverage decreasing each day. As things dry out, the primary threat of thunderstorms will switch from heavy rainfall to gusty outflow winds up to 50 mph.

High pressure sets up over Utah this weekend bringing hot and mostly dry conditions. Temperatures will run around 10 degrees above normal, but with less moisture in the air, you can expect more of a "dry heat" compared to what we've endured lately.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 515 PM MDT Tue Jul 28 2026

Storms continue to gradually diminish for the evening. Cloud cover will begin to lighten up into the overnight hours, with some mid-level development by Wednesday afternoon. Winds will return to light and terrain driven during the overnight period. Shower and storm chances return by 17-18Z Wednesday. Storms will begin to initialize off the higher terrain, with the potential for those storms to spread down towards adjacent valleys. Included PROB30 groups to account for that. Primary threats with these include lightning, heavy rainfall, and gusty outflow winds.

HYDROLOGY

Issued at 1130 PM MDT Tue Jul 28 2026

Scattered slow-moving thunderstorms capable of producing heavy rainfall will develop each afternoon through at least midweek. Rainfall rates of 1-2" per hour will be possible, potentially even greater for brief periods of time with stronger storms. These rates could lead to flash flooding and debris flows, especially over steep terrain and recent burn scars. Saturated soils from consecutive days for rainfall will increase the potential for flash flooding as well.

As a reminder: Keep an eye on our forecasts and stay tuned for updated hydrology alerts if visiting or if you reside near 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.