891
FXUS65 KGJT 290938
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
338 AM MDT Sun Jun 29 2025

.KEY MESSAGES...

- Mountain storms develop each afternoon with coverage
  increasing throughout the week ahead.

- Unseasonably warm conditions remain in place through mid
  week.


&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 333 AM MDT Sun Jun 29 2025

Isolated to scattered storms return to the high terrain this
afternoon, especially along and north of I-70. While the
atmosphere is still rather dry with high pressure building in,
enough moisture is progged to be present to produce convection.
With the dry near-surface layer remaining in place, gusty
outflow winds up to 50 mph and fire starts are the primary
thunderstorm threats today. Wetting rains are not anticipated
(<20% chance).

Temperatures remain unseasonably warm area wide with afternoon
highs 5 to 10 degrees above normal for late June.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 157 PM MDT Sat Jun 28 2025

High pressure will still be overhead Monday as a deep area of
low pressure spins off the California Coast. Models have been
fairly consistent in this regard. During the day Monday, PWATs
slowly increase across the area and with this increased
moisture, chances (30 to 40%) also increase for a few showers or
storms to form, mainly along the Continental Divide. The low
pressure will drift eastward some on Tuesday, just enough to
start advecting some deeper moisture into the region under broad
southwesterly flow. PWATs by Tuesday afternoon/evening will
reach anywhere from 150 to 170% of normal early July values. As
of now, the best chances (still 30 to 40%) exist over the San
Juans for showers and storms. By Wednesday, the low opens up and
becomes an upper level trough. Minor pieces of energy will also
be rotating up from the south. PWATs Wednesday afternoon will
reach 200% of normal and as these 2 features interact with the
moisture, an increase in showers and storms is anticipated. The
deterministic GFS and EC are on board with this scenario while
the NBM is still not as aggressive. Not surprised as there is
still plenty of time to nail down the specifics. That being
said, the trough pushes through on Thursday bringing another
round of precipitation to the eastern UT and the Western Slope.
PWATs remain well above normal at 200% but it appears the
deepest moisture may shift to the central and northern portions
of the CWA. A rather weak, transitory ridge then builds in for
Friday and Saturday. Some lingering moisture will allow some
convection to fire in the afternoon and evening and we`ll be
back to the Divide for favored locations. As mentioned, some
discrepancies remain with this forecast but confidence does
continue to increase for a period of unsettled weather for
midweek.

Temperatures through Tuesday will remain above normal and then
drop to near normal Wednesday onwards thanks to increased cloud
cover and precipitation.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 938 PM MDT Sat Jun 28 2025

Some leftover cloud cover on the terrain will continue to thin
and winds will subside back to light and terrain influenced for
the overnight hours. VFR conditions are expected to hold on
across the region through this TAF period thanks to the ample
dry air and additional high pressure building back overhead
Sunday. Winds will run west to northwest Sunday afternoon with
some afternoon gusts to around 20 mph. Clouds will sprout on the
terrain. A non zero precipitation chance will continue on the
terrain of northeast Utah and northwest Colorado Sunday
afternoon. Showers will drift off terrain and quickly dissipate,
with gusty outflow winds the main concern for airfields in
adjacent valleys.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...KAA
LONG TERM...TGR
AVIATION...TGJT