087
FXUS65 KGJT 182343
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
543 PM MDT Fri Jul 18 2025

.KEY MESSAGES...

- Showers and thunderstorms continue Saturday around the region.

- Flash flooding remains a threat for burn scars and flood prone
  areas.

- Mountain showers and thunderstorms remain in the forecast into
  next week.

- Smoke will continue to ebb and flow around the forecast area
  along with wildfire activity.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 307 PM MDT Fri Jul 18 2025

A recognizable summer regime has taken up residence here on the West
Slope. Subtropical moisture continues to work north across the Four
Corners along the western perimeter of broad high pressure anchored
over the southern CONUS. A training line of convection has formed
along a Monticello, UT to Grand Junction heading. Terrain
enhancements by the Abajos and La Sals in concert with tropical
moisture has kept this line a hotbed of convection this afternoon.
Elsewhere, showers have been less impressive. Shower activity will
continue on the terrain into early evening then decay quickly
towards sunset.

The upper level regime holds on Saturday. The progressive, zonal
pattern to our north drags a shortwave through Saturday afternoon.
This is expected to keep shower chances for pretty much everywhere
north of the Colorado River/I-70 corridor, while south of there,
terrain based convection will produce additional showers and
thunderstorms. Ensemble guidance has picked up on some dry slotting
in southeast Utah and southwest Colorado, leading to some
inconsistency with precipitation chances there. Ensembles also drop
PWAT`s Saturday. While showers may not have the punch they had
today, there should still be ample fuel for mountain showers and
thunderstorms with PWAT`s around 0.60" across the region. This
should continue to help with wildfire smoke, as the Deer Creek,
Turner Gulch, and South Rim Fires received rainfall within their
perimeters this afternoon. Temperatures will trend near to a few
degrees below normal, given the cloud cover. Once again, shower
activity will taper off near sunset Saturday evening.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 307 PM MDT Fri Jul 18 2025

On Sunday dry air will still be in place, which should limit
afternoon convection. Although the high terrain can expect isolated
to scattered showers and storms. Highs come up a few degrees in the
drier air. On Monday there are signs that moisture surges back in
from the south as heights increase due to a PacNW trough. This
should result in another uptick in showers and storms around the
area into Tuesday. The uncertainty is how that PacNW trough evolves,
because as it ejects and breaks apart flow over us will change. With
dry air not far to our west it will only take an slight shift to
west northwest to advect that air into the area. Ensembles are
showing that eventually the dry air filters in later this week.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 543 PM MDT Fri Jul 18 2025

Showers and thunderstorms have dissipated for the most part over
the region, though KHDN, KMTJ, and KVEL may see occasional
rainfall over the next couple hours. Cigs may drop below ILS
breakpoints at some higher elevation terminals into the evening
though, particularly at KASE and KEGE. Tomorrow, storms return,
impacting mostly the high terrain. Gusty afternoon winds
upwards of 25 mph are possible across portions of the region,
with stronger gusts expected near thunderstorms.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...LTB
LONG TERM...KJS
AVIATION...TGJT