textproduct: Grand Junction

KEY MESSAGES

- Hot, dry, windy conditions will produce pockets of critical fire weather conditions for the West Slope Monday, favoring southwest CO.

- Near normal temperatures Monday will return to 10 degrees above average this week.

- Afternoon showers and thunderstorms will remain in the forecast each afternoon on the mountains through, at least, mid-week.

DISCUSSION

Issued at 118 PM MDT Sun May 31 2026

Broad cyclonic flow across the West is taking advantage of weak moisture this afternoon, mostly north of I-70. A few orographic enhanced showers have developed, including a few lightning strikes for northeast UT. Given some weak shear and CAPE on the Grand Junction sounding this morning, a weak capping inversion in the mid layers seems to be suppressing shower development. Low pressure begins to lift out of the northern Rockies Monday, pulling some stronger southwesterly winds across the Four Corners Monday afternoon. Single digit relative humidities and gusty winds will produce some local fire weather conditions. Did not issue any highlights, as this remains too localized to require a warning.

A ridge of high pressure amplifies on the Great Plains Monday and Tuesday. This works in concert with the leeside low to pull some return flow moisture northward into our CWA. This moisture will increase slowly through Wednesday, as shortwaves working across the northern tier states chip away at the ridge. Afternoon showers and thunderstorms on the terrain will continue under this regime. A bowling ball low working across Baja late Wednesday will shunt moisture eastward and likely help to pull some cooler drier air in, suppressing showers some late week.

Southerly flow will keep temperatures on the warm side this week, as our afternoon highs surpass 10 degrees over normal each afternoon. Cloud cover and showers will likely eat into this trend for some mountain valleys, but hot and dry should be the widespread expectation. Deterministic models are gathering around a deeper low working ashore in the PACNW Saturday that could promise some late week pattern shifts, including robust winds and critical fire weather conditions. For now, we enjoy some summer-adjacent weather conditions to kick off June.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1142 AM MDT Sun May 31 2026

VFR conditions are forecast through the TAF period. Passing showers and isolated storms are possible this afternoon, mainly at terminals along and north of I-70.

GJT WATCHES/WARNINGS/ADVISORIES

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