textproduct: Grand Junction

KEY MESSAGES

- Critical fire weather conditions persist Sunday and continue at least through Wednesday.

- High-end fire weather conditions are likely for portions of the region on Tuesday due to very low relative humidity and strong winds.

- Temperatures hold above average through Tuesday, before trending down late week to near normal.

DISCUSSION

Issued at 1245 PM MDT Sat Jun 6 2026

The digging trough anchored over the West this afternoon, continues to carve out strong southwesterly flow for the region. This has pushed current temperatures well over normal and we've still got a couple of hours of heating that will push us to near record values across the region this afternoon. While the airmass remains persistently dry at the surface, strong orographic flow has produced a widespread cumulus field on the terrain, including a few showers. A few of these showers have produced lightning strikes. This threat continues through early evening, but quickly diminishes as the daytime instability wanes. Dry thunderstorms continue to pose a threat to the region Sunday as the trough digs into a weak pulse of Pacific moisture that it lifts northeastward over the Great Basin. Increased the POPs for northeast UT and northwest CO, as this appears to be the best target of opportunity for shower development/convective initiation on Sunday. Elsewhere on the terrain, showers remain in the forecast with much more localized coverage increasing uncertainty. Fire weather highlights continue Sunday, with a critical fire weather regime favorable to new fire starts thanks to lightning.

The blocking ridge downstream continues to reamplify as cyclonic flow over the West drives height fields upward. This keeps us anchored beneath a hot, dry, windy southwesterly flow and additional critical fire weather. Fire weather watches on Monday and Tuesday were left in place, and will likely be upgraded in subsequent packages. Surface wind forecasts on Tuesday remain concerningly high, given the single digit relative humidity in place. Strong winds will continue Wednesday, as the main trough shows signs of pushing across the Rockies. This will introduce some cooler temperatures(i.e. near normal). Winds will subside some Thursday, with stronger gusts hanging on over the Continental Divide through week's end. Critical fire weather conditions show some signs of contracting towards just the mountain zones Friday thanks to lighter winds. Warm and dry conditions will continue though, with some isolated mountain showers possible.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 530 PM MDT Sat Jun 6 2026

Scattered Cu skies will clear out as sun sets and the widespread gusty winds of 20 to 30 mph will also diminish as the evening wears on. Tranquil conditions are expected overnight with VFR remaining the predominant flight condition though some mid to upper level clouds will be on the increase near daybreak onwards. Tomorrow, more of the same though gusty winds will be a little stronger than those seen today.

FIRE WEATHER

Issued at 1245 PM MDT Sat Jun 6 2026

A long stretch of critical fire weather persists through Thursday. This is being prompted by strong winds and dry surface conditions beneath a strong sustained southwesterly flow aloft. Through Monday, winds will gust 25-35 mph with isolated values to 40 mph possible and relative humidities will be near or in the single digits. Fire zones with critical fuels have been placed under Red Flag Warnings or Fire Weather Watches, with upgrades likely for the watches in subsequent forecast packages. Isolated dry thunderstorms could develop on Sunday due to a pulse of moisture lifting into the region as the trough out west deepens. This could pose problems for new fire starts in northeast UT and northwest CO. Critical fire weather conditions amplify Tuesday, with an increase concern for high-end critical fire weather conditions due to the stronger winds beneath a tightening pressure gradient and no relief to single digit relative humidity. The majority of the region will see gusts of at least 35 mph. However, the lower Yampa River Basin, Uinta Basin, Utah Grand Flat, and Four Corners region, winds are forecasted to reach as high as 50 mph in concert with the single digit relative humidities. Multiple forecast runs have been consistently painting these stronger winds, leading to increasing confidence in the high-end nature of Tuesday's fire weather potential. Red Flag conditions likely persist for portions of the region on Wednesday and Thursday as well, with temperatures recovering back to near normal.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Red Flag Warning until 9 PM MDT this evening for COZ200-202- 203-207-290-292. Red Flag Warning from 10 AM to 10 PM MDT Sunday for COZ200-202- 203-205-207-290>293. Fire Weather Watch from Monday morning through Tuesday evening for COZ200-202-203-205-207-290>293. UT...Red Flag Warning until 9 PM MDT this evening for UTZ486-487- 490-491. Red Flag Warning from 10 AM to 10 PM MDT Sunday for UTZ486-487- 490-491. Fire Weather Watch from Monday morning through Tuesday evening for UTZ486-487-490-491.