textproduct: Grand Junction

KEY MESSAGES

- Expect terrain-based showers and thunderstorms each afternoon this week, favoring the San Juans, but spreading north by the weekend.

- Flash flooding on burn scars will be possible where there is localized heavier rainfall.

- Daytime highs cool throughout the week, returning to near- normal for most areas by Friday.

DISCUSSION

Issued at 1052 PM MDT Tue Jul 14 2026

Models are in good agreement with satellite imagery with broad high pressure across the northern Plains into the Great Lakes region bringing clear skies to much of the CONUS east of the Rockies, and low pressure circulation across the southern states under partly to mostly cloudy skies. To the west a deep plume of moisture has pushed north around the western flank of the high into the Intermountain West. Some of this moisture is working east in under the high to produce isolated to scattered showers and thunderstorms across eastern Utah and Western Colorado favoring the higher terrain to the south and west. Look for this moisture to continue to slowly work its way into the region with convective activity spreading farther north and east into the mountains each day through the remainder of the week. We can expect to see pwats above an inch across eastern Utah and much of Western Colorado by Saturday. Of concern is that these afternoon storms will be slow moving due to the weak flow aloft under the high which increases the risks for higher amounts of rainfall possible on recent fire scars, especially in the southern mountains where the moisture is deepest. Stay tuned for forecast updates on these afternoon and evening showers and thunderstorms, and be alert to the weather and any weather warnings if you are in the area of a recent fire.

Temperatures will cool over the next few days as increasing clouds limit diurnal heating and afternoon showers cool the region. Tomorrow will have highs five to ten degrees above normal across the northern and central areas while the southern areas will continue to run near normal. Thursday through the weekend temperatures will generally be near normal across much of the region to about five degrees above normal across the northern areas as the moisture pushes north. Guidance is suggesting deeper moisture moves in to cool temperatures another five degrees going into mid next week with mostly cloudy skies through the late morning and afternoon, the peak of diurnal heating. At a week out it's a stretch, but we can always hope...

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 518 AM MDT Wed Jul 15 2026

Convective debris and old outflow boundaries continue to drift through the area which could lead to some isolated light showers this morning. VFR prevails and this will continue over the next 24 hours. MVFR conditions have a low probability of occurring tomorrow afternoon as an uptick in thunderstorm activity...with moderate to heavy rainfall rates...occurs over the southern CWA...including the KTEX...KGUC and KDRO airfields. Outflow boundaries from storms could create a difficult wind forecast through the evening quickly changing directions and speeds will be possible.

GJT WATCHES/WARNINGS/ADVISORIES

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