textproduct: Grand Junction

KEY MESSAGES

- Generally dry conditions with near-normal temperatures are expected through Monday, although an isolated mountain shower or two is possible.

- A frontal boundary could deliver some additional showers Tuesday and Wednesday next week.

- A warming trend will continue through the week. Triple digits will remain confined to the Four Corners and low desert valleys.

DISCUSSION

Issued at 1144 AM MDT Sun Aug 16 2026

Residual, but limited moisture may result in a shower mainly along the Divide this afternoon. Otherwise most locations will be dry. The same can be said about tomorrow. A weak frontal boundary sets up across the Northern Great Basin Tuesday into Wednesday, tightening up the surface pressure gradient across northeast Utah and northwest Colorado. Some gustier winds of 20-30 mph will be possible in this region, although surface relative humidity values will be high enough that critical fire weather conditions are not anticipated. Some extra moisture accompanies this frontal boundary, with PWAT values forecast to be 100-150% of normal across the region, with the best moisture north of I-70. With a combination of orographics and a bit of forcing from the frontal boundary, some isolated to widely scattered showers and thunderstorms will be possible across the higher terrain Tuesday and Wednesday afternoon. Slightly above normal moisture lingers through the end of the work week, leading to lower-end (20-30%) chances of showers or thunderstorms over the higher terrain each afternoon. The main threats with these storms will be gusty outflow winds and lightning, although a brief heavy downpour cannot be ruled out.

High pressure settles over the Four Corners Thursday into Friday, ushering in a drying and warming trend. By the end of the week, high temperatures are expected to run around 10 degrees above normal, with triple digits across the lower desert valleys and the Four Corners. Friday into the weekend, models are indicating a trough moving into the Pacific Northwest will nudge the high eastward once again, returning weak monsoonal flow into the Four Corners.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1137 AM MDT Sun Aug 16 2026

VFR conditions are expected to remain in place through the TAF period. Some mid level clouds are forming on the terrain this afternoon, but breakpoint ceilings are not expected. Winds will pick up during the peak of afternoon heating, leading to some gusts around 20 mph, but then diminish quickly early this evening. A non zero chance for a shower or two on the Uintas and up against the Continental Divide remains. Gusty outflow winds around these dry showers will be the primary threat to aviators. Light winds and clear skies will close out this period Monday morning.

GJT WATCHES/WARNINGS/ADVISORIES

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