textproduct: Grand Junction

KEY MESSAGES

- Smoke may continue to be visible across the region due to fires burning in Utah, especially this evening and tomorrow morning.

- Red Flag Warnings are in effect through 10 PM for southeast Utah, southwest Colorado, and along the Divide north to the Wyoming Border. Critical fire weather conditions become more localized tomorrow.

- Chances for showers and thunderstorms increase tomorrow, and will become more widespread on Thursday.

- Hot, dry, and windy conditions return on Friday. Fire Weather Watches are in effect on both Friday and Saturday.

DISCUSSION

Issued at 248 PM MDT Tue Jun 23 2026

WILDFIRE SMOKE:

Periods of smoky skies are expected today and tomorrow. This is primarily due to two wildfires in Utah, the Iron Fire and the Cottonwood Fire. Mostly zonal flow will transport this smoke across eastern Utah and western Colorado through tomorrow, and potentially beyond. This may impact air quality at times, so be sure to stay informed about smoke and air quality information.

FIRE WEATHER AND MIDWEEK MOISTURE:

Hot, dry, and windy conditions will persist through today and some of tomorrow. Red Flag Warnings remain in effect today for much of the Four Corners area and along the Divide through the evening. Critical fire weather conditions become more localized tomorrow as a plume of moisture moves in from the southwest and raises relative humidities. Due to already borderline wind gusts and the potential for wildfire smoke to reduce the mixing down of stronger winds aloft, and more localized coverage, Red Flag Warnings have not been issued for tomorrow. However, the greatest coverage of these localized conditions looks to be along and north of I-70 conditions.

Elevated moisture starting tomorrow afternoon increases the risk of dry thunderstorms, but will also increase the chance of wetting rains. After the long stretch of dry surface conditions, virga and dry thunderstorms are expected at first, but as more moisture advects into the region wetting rains will become more likely. This increased moisture will raise relative humidities above critical fire weather thresholds on Thursday. Precipitation from this moisture will be possible through Thursday night.

Drier air moves in on Friday, dropping relative humidities again. Additionally, strong winds are forecast as a closed low in the Pacific Northwest brings a much stronger pressure gradient and jet aloft to our region. This is expected to raise surface wind gusts significantly above critical fire weather thresholds. So, Fire Weather Watches have been issued for Friday and Saturday.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 516 PM MDT Tue Jun 23 2026

Smoke will continue to traverse the region this evening through at least tomorrow morning. Opted to include TEMPO groups for KGJT and KCNY where I suspect the smoke could cause visibility to drop. Gusty winds will begin to die down as we move into the evening hours. Winds will then resume terrain driven flow through the overnight period. Gusts will pick up again tomorrow afternoon, within the 20-25kt range. Cloud coverage will also begin to increase tomorrow afternoon through the evening as some moisture begins to enter the region. Aside from visibility concerns associated with smoke, VFR conditions are expected to prevail through the TAF period.

FIRE WEATHER

Issued at 248 PM MDT Tue Jun 23 2026

Critical fire weather conditions will continue through the evening today where Red Flag Warnings are in effect. Tomorrow critical fire weather conditions become more localized, but the greatest coverage of these localized conditions will be near and north of I-70. A moisture push from the southwest tomorrow will increase chances of dry thunderstorms and wetting rains. Dry thunderstorms and virga is most likely during the initial onset of showers and storms, as dry surface conditions will make it difficult for rain to reach the ground. As atmospheric moisture increases during the day, chances of wetting rains will increase as well. Precipitation is expected to continue through Thursday night. This moisture will raise relative humidities above critical fire weather thresholds on Thursday, but drier conditions return by Friday. The return of drier air, alongside a strong increase in wind gusts, raises fire weather concerns for Friday and Saturday. Saturday looks to be the most concerning day, with widespread single digit relative humidities and gusts of 35 to 50 mph currently forecast. Fire Weather Watches have been issued for both Friday and Saturday.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Fire Weather Watch from Friday afternoon through Friday evening for COZ200-202-203-207-290. Red Flag Warning until 10 PM MDT this evening for COZ201-205- 207-290>295. UT...Red Flag Warning until 10 PM MDT this evening for UTZ491. Fire Weather Watch from Friday afternoon through late Saturday night for UTZ486-487-490-491.