textproduct: Grand Junction

KEY MESSAGES

- Smoke may continue to be visible across the region due to fires burning in Utah.

- Red Flag Warnings are in effect from noon to 10 PM for southeast Utah, southwest Colorado, and along the Divide north to the Wyoming Border.

- Chances for showers and thunderstorms increase Wednesday becoming widespread Thursday.

- Hot, dry, windy conditions return for the weekend and into next week.

DISCUSSION

Issued at 1043 PM MDT Mon Jun 22 2026

ANOTHER HOT, DRY, WINDY DAY:

There is little change in the synoptic pattern characterized by low pressure system located to the north across southern Canada, and high pressure to the south along the Mexican border with eastern Utah and Western Colorado under a dry zonal flow. There have been a few isolated showers across the higher terrain north of I-70 mostly in the form of virga. High resolution models are indicating tomorrow looks to have fewer clouds with any possible convective activity only along and north of the Wyoming border or along and east of the Divide. Winds do pick up a bit tomorrow with gusts to 35 mph, and with the dry airmass in place, warrant wider coverage of Red Flag Warnings from noon to 10 PM for southeastern Utah, southwestern Colorado, and areas along the Divide to the Wyoming Border. The desert valleys will see more triple digit daytime highs tomorrow and possibly Wednesday. If recreating outdoors, stay hydrated and take frequent breaks in the shade.

MOISTURE CHANCES MID WEEK:

Probably the most significant change in the forecast is the plume of moisture moving up from the Gulf of Cortez around the high pressure to our south arriving sooner than had been forecast, as soon as Wednesday morning. With increased clouds, expect temperatures to drop a few degrees from tomorrows highs, but the moisture brings an increased risk for dry lightning, especially for the Abajo and La Sal Mountains, the Uncompahgre Plateau, and to the north over the Tavaputs and up into the Elkhead Mountains. Chances are marginal at this point with probabilities running 10-20%, so pushed off issuing any products for dry lightning until we get another look tomorrow. Stay tuned for updates on this one. As you move into the Colorado mountains, closer to the Divide, chances for wetting rain increases thereby reducing the chances for dry lightning.

As moisture moves in from the west, look for isolated showers and thunderstorms over the higher terrain of eastern Utah and far western Colorado the late morning becoming more scattered going into the afternoon over the San Juan Mountains to the south. By Wednesday evening these showers and thunderstorms will become more widely scattered to widespread over the higher terrain across the region. These storms will diminish overnight into Thursday, but with diurnal heating, will become widespread across the region favoring the higher terrain. Most of the region will see some rain from this system, if only a few hundredth inch with most of the higher terrain receiving wetting rain, a tenth inch or more.

CRITICAL FIRE WEATHER RETURNS FOR THE WEEKEND:

A deep low pressure system descends down through the Pacific Northwest Friday evening with an associated trough dropping into the Great Basin Saturday. This sets up a strong southwesterly flow across the region with winds gusting 40 to 50 mph each afternoon going into next week. These winds will sweep any residual moisture out of the region bringing a return of widespread critical fire weather conditions to eastern Utah and Western Colorado through the weekend and into next week. You'll want to stay tuned to updates on this through the week.

AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/

Issued at 1149 PM MDT Mon Jun 22 2026

Some scattered light showers continue to move across the north with potential for breezy conditions at times but these should dissipate in the early morning hours. Smoke from wildfires in Utah and Nevada will track across the region resulting in hazy skies for most terminals but should not impact airport operations for most locations, so did not include in most TAFs. KVEL and KCNY are the exception where smoke looks to be tracking towards the terminals at this time so included mention of smoke at these eastern Utah sites for the overnight periods. Winds will generally be light and terrain driven overnight with afternoon gusts Tuesday in the 20 to 30 kt range under mostly clear skies.

FIRE WEATHER

Issued at 1043 PM MDT Mon Jun 22 2026

A tightening pressure gradient will give way to more widespread critical fire weather conditions Tuesday with Red Flag Warnings in effect for southeastern Utah, southwestern Colorado, and along the Divide north to the Wyoming Border. Gusts will be upwards of 35 mph with minimum humidities in the low teens and single digits. Daytime highs are also expected to be in the triple digits for most desert valleys at this time. Some mid to high level moisture moves into the region Wednesday with a risk of dry lightning and erratic virga outflow winds Wednesday through Friday. Held off on issuing highlights for Wednesday as much uncertainty still exists on coverage for dry thunderstorms. Much of the higher terrain across the region will see wetting rain Thursday, especially the central and southern mountains. The weekend will see a return of widespread critical fire weather conditions with winds gusting 40 to 50 mph. Continue to monitor our forecast as updates are made.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Red Flag Warning from noon to 10 PM MDT Tuesday for COZ201-205- 207-290>295. UT...Red Flag Warning from noon to 10 PM MDT Tuesday for UTZ491.