textproduct: Grand Junction

KEY MESSAGES

- Fire weather conditions alleviate today and Sunday as winds weaken. Fuels and surface conditions are still dry though. Obey all fire restrictions.

- Above normal temperatures make a return for the holiday weekend and beyond.

- Isolated showers and thunderstorms could return as early as Sunday, with coverage increasing Monday and Tuesday.

- Chances for wetting rain remain low, instead dry lightning poses a threat to new fire starts early next week.

DISCUSSION

Issued at 1156 AM MDT Sat Jul 4 2026

DRY AND HOT THIS HOLIDAY WEEKEND INTO NEXT WEEK:

Dry conditions will be present this holiday weekend with temperatures heating up as a ridge of high pressure slides over the region and the upper level jet lifts well north of the area with the strongest winds across the Northern Rockies and the U.S.-Canadian border as a more robust trough moves across the Canadian Prairies. The good news is that winds across our region this weekend into the coming week will be much less than our recent stretch due to less gradient winds overhead, resulting in a reprieve from widespread critical fire weather conditions. Localized fire weather conditions are still possible across the Four Corners with gusts 20 to 25 mph but overall, winds should be much less than previous days even though temperatures will be rising towards 5 to 10 degrees above normal. Highs in lower valleys will be rising well into the 90s with some triple digit heat eventually showing up across some lower desert valleys especially by mid to late next week. Smoke from nearby wildfires will continue to linger and this could have an impact on our temperatures being overestimated in some areas. Regardless, it will be hot this weekend heading into the coming week.

Even though fire weather conditions will have alleviated this holiday weekend due to weaker winds, dry vegetation and surface conditions will still pose risks of new fire starts. It is imperative to be aware of and obey all fire restrictions, and be mindful of wildfire prevention tips.

MOISTURE ARRIVING, LITTLE RAIN, AND DRY THUNDERSTORM POTENTIAL:

Enough moisture, forcing and instability remains across our northern areas today for isolated storms to develop over the higher terrain north of I-70...in particular the eastern Uintas and Flattops. Otherwise, dry conditions remain. Attention turns towards moisture advecting northeastward around the high from the Baja Peninsula and SoCal and tracking across the Great Basin and western slope late Sunday into early next week. There are some slight timing differences with onset of this moisture (GFS ensembles being a bit earlier Sunday where the EC ensembles hold off until Monday). The ensembles do however agree that this moisture peaks on Tuesday with PWAT anomalies in the 120 to 140 percent of normal range. Regardless, this moisture is elevated and the low levels remain dry. So this unfortunately draws up concerns for dry thunderstorm potential (see Fire Weather section for more details). Sunday appears more isolated in coverage along the spine of the divide with Monday and Tuesday having better coverage across the western Colorado mountains, particularly the San Juans. Wetting rain chances do appear better in the San Juans Monday and Tuesday but there is uncertainty with regards to whether it will be enough as low levels remain dry. The residence time of this moisture isn't long enough either for much precipitation to overcome the dry low levels as drier air looks to move back in and push this mid level moisture out by Thursday. So dry thunderstorms remain more of the concern here with potential for new fire starts as well as gusty outflow winds. Coverage becomes more isolated by Thursday and Friday and a ridge builds in and amplifies across the Great Basin by weeks end. Stay up to date on the latest forecast as more hi-res guidance comes in and we get a better handle on this dry thunderstorm potential early next week.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1156 AM MDT Sat Jul 4 2026

Winds are beginning to gradually increase across the region, but will generally remain near or below 10 kts at most sites today. A few sites, including KTEX, KDRO, KGUC, and KHDN, will gust between 15 to 20 kts this afternoon. Wildfire smoke is expected to reduce visibility during the TAF period, mostly south of I-70, and will potentially cause periods of MVFR conditions at KMTJ and KTEX. Winds will become light and terrain driven tonight.

FIRE WEATHER

Issued at 1156 AM MDT Sat Jul 4 2026

Fire weather conditions reach their first lull in quite some time today as weak flow spreads out across the region, prompting gusts to generally fall below Red Flag thresholds. With the atmosphere still very dry though, look for surface relative humidities to remain in the low teens to single digits.

Next week, the region sees its first glimpse of notable moisture in over a week. The caveat appears to be that the bulk of this moisture lingers in the mid-level atmosphere. The initial push of moisture will creep in from the south on Sunday. Inverted-V atmospheric profiles with relatively moist mid- layers could prompt some pyroconvection over hot spots on Sunday as a result. Over the following three days (Monday through Wednesday) surface moisture will be peaking. Unfortunately this doesn't mean a whole lot as most valleys won't get much higher than 10-20% RH with any soothing RH values reserved for the higher elevations. As such, concerns are increasing that we could be facing another multi-day stretch of dry lightning focused around the slopes of the San Juans, albeit other locations across the CWA are poised for slight chances of thunderstorms as well (<35% chance). This will threaten new lightning ignitions and exacerbated wildfire conditions near virga showers and any gusty outflow winds that they produce.

To leave you off with a bit of good news though, beyond Wednesday spanning at least through the end of the work week, though RH falls off once again, the overarching upper-level pattern does not appear to become conducive to critical fire weather conditions as flow remains on the weaker side. This pattern is relatively well-agreed upon amongst ensembles as well. Increasing heat and dryness will still likely pose some fire weather issues, but without the strong winds to accompany, early indications are critical fire weather conditions may be avoided. There is still plenty of time between now and then though, so stay tuned for future forecast updates in case models begin to trend in another direction.

GJT WATCHES/WARNINGS/ADVISORIES

CO...None. UT...None.