textproduct: Grand Junction

KEY MESSAGES

- Record heat and predominately dry conditions move in for the weekend and early next week with localized critical fire weather conditions.

- Chance for showers return to the southern mountains and valleys mid to late next week.

DISCUSSION

Issued at 1059 PM MDT Fri Jul 31 2026

HOT AND DRY THIS WEEKEND INTO NEXT WEEK:

High pressure will strengthen and anchor itself across the Desert Southwest this weekend, reinforcing this drier air mass and allowing temperatures to climb a bit higher well into the triple digits for the valleys of eastern Utah and lower western Colorado. We will be under a northerly flow and a more stable regime, so it will be pretty hard pressed to get much convection or shower activity going. Storm activity seems to favor areas east of the divide, with the eastern and far southern San Juans standing the best chance of isolated storms potentially drifting south off the terrain Saturday afternoon and again on Sunday afternoon. Given the much drier air mass, lack of upper level support and lack of forcing...do not expect any activity to last very long and will be more conducive to gusty outflow winds and lightning rather than any wetting rain. Regarding the heat, record high temperatures are possible for many locations with low relative humidity in the teens and single digits for the lower valleys, giving us a bit of a reprieve from the monsoonal moisture through at least early next week. On Monday, a trough will track across the Northern Rockies into the Plains, which could introduce some clouds and a brief suppression of the high pressure. It appears like storms would favor areas east of the divide while the western slope remains hot and dry, but the higher terrain of the divide could see some isolated afternoon storm activity. Extreme Heat Warnings and Heat Advisories remain in effect this weekend through Monday for our eastern Utah valleys and Grand Valley in west-central Colorado. See product for details and exact timing for those particular locations.

MOISTURE POTENTIAL MID TO LATE NEXT WEEK:

Looking ahead in the week, the pattern becomes a bit disorganized with the high pressure remaining across the Desert Southwest and Great Basin but becoming a bit squashed and not as strong mid to late next week. It appears that we will slowly introduce some moisture across the Four Corners as it seeps in underneath this ridge from Arizona and New Mexico. This will allow for a bit more afternoon thunderstorm development over the southern mountains at first with that moisture and storm coverage potentially slowly creeping northward by late next week. The northern stream will also become more active with a few passing shortwaves across the northern tier of states that could help provide the needed forcing. This is a low confidence forecast on this moisture return and extent of storm activity. Otherwise, temperatures look to remain hot around 10 degrees above normal.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 530 AM MDT Sat Aug 1 2026

High pressure will dominate through the TAF period with VFR conditions at all terminals. Afternoon winds will gust to around 20 mph in a few locales, but return light and variable by early this evening. Clouds will be minimal, but a few mid and high clouds will stream across the ridge of high pressure through the afternoon, clearing after dark again.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Heat Advisory from noon Sunday to 9 PM MDT Monday for COZ006. UT...Heat Advisory from noon Sunday to 9 PM MDT Monday for UTZ022. Heat Advisory from noon to 9 PM MDT Sunday for UTZ024. Extreme Heat Warning from noon today to 9 PM MDT Monday for UTZ027-029.