textproduct: Grand Junction

KEY MESSAGES

- Critical fire weather conditions are expected to continue through the work week.

- Critical fire weather conditions abate this weekend, as winds lighten and temperatures surge back above normal for the holiday weekend.

- Hot and dry conditions persist with little chance for wetting rains.

DISCUSSION

Issued at 135 PM MDT Tue Jun 30 2026

The broad trough swinging through the Great Basin this afternoon has produced a couple of isolated lightning strikes to the west of the Uinta Basin. The antecedent hot and dry conditions make this a concerning situation for lightning starts. This cyclonic flow will remain anchored over the West the rest of the week. A couple additional shortwave ripples will likely spell out a similar risk situation for new lightning starts each afternoon, until we can eject the trough out of the region. Breezy southwesterly flow will continue to produce critical fire weather conditions as well. Fire Watches were upgraded to Warnings for Wednesday and additional Watches were issued for Thursday as a result.

A slightly cooler air mass in the gut of the trough will keep high temperatures down until we get rid of the trough. Lighter winds will accompany the trough's exit this weekend. Unfortunately though, temperatures surge above normal for the holiday weekend and further reinforce the hot and dry pattern. The hot and dry forecast will keep our eyes open for any hint of moisture intrusion that high pressure can push northward. Some hints of this turn up early next week in the deterministic models. This remains a tenuous situation as we look for measurable precipitation without dry lightning.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1121 AM MDT Tue Jun 30 2026

Expect VFR conditions across the region through the TAF period. Southwest winds around most terminals will gust 20-30 knots, with some localized areas seeing stronger winds gusting up to 40 knots expected in the Four Corners region. Smoke in the area is becoming less of an issue, but visibility reductions cannot be ruled out from time to time.

FIRE WEATHER

Issued at 135 PM MDT Tue Jun 30 2026

Red Flag conditions are expected through at least Friday before the stagnant trough driving the dry and windy setup finally appears to break down into more zonal flow with weaker winds into the weekend. For most days, fire weather appears marginal to moderate with single-digit relative humidities and gusts around 25-35 mph. A series of weaker upper level disturbances could touch off some dry thunderstorms across northeast UT and northwest CO this week. While this remains a very isolated chance, the persistent critical fire weather pattern will lend a hand to lightning started wildfires this week. Wetting rains remain highly unlikely through the week.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Red Flag Warning until 9 PM MDT this evening for COZ200>203- 205-207-290>294. Red Flag Warning from noon to 8 PM MDT Wednesday for COZ205- 207-290-292-294. Fire Weather Watch from Thursday afternoon through Thursday evening for COZ205-207-290>295. UT...Red Flag Warning until 9 PM MDT this evening for UTZ486-487- 490-491. Red Flag Warning from noon to 8 PM MDT Wednesday for UTZ491. Fire Weather Watch from Thursday afternoon through Thursday evening for UTZ491.