180
FXUS65 KGJT 141145
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
545 AM MDT Mon Jul 14 2025

.KEY MESSAGES...

- Above-normal temperatures remain status quo through the seven-
  day forecast.

- Outflow winds and dry lightning remain a threat today as
  thunderstorm coverage increases across the western Colorado
  terrain.

- Coverage of afternoon showers and storms will continue through
  the week, increasing chances for wetting rains and less
  wildfire smoke.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 425 AM MDT Mon Jul 14 2025

A decaying outflow boundary and some orographics tapped into some
moisture and kept cloud cover along the Continental Divide and on
the San Juans overnight. Rainfall was not noted anywhere, despite a
few radar returns in the 550 corridor, likely just cloud cover.
Satellite water vapor imagery is painting a plume of moisture across
much of the West Slope. Lower levels look pretty anemic, aside from
the San Juans and the Divide. This should be the target of
opportunity for shower and storm initiation today. A passing
shortwave across the northern half of the CWA could lend a hand in
some orographic enhancement too. Ensemble forecasts show around half
an inch of PWAT across much of the region today. This should be
enough to see another afternoon of terrain based showers and
thunderstorms. Aforementioned water vapor locations look pretty spot
on for shower development. Coverage on the San Juans will look the
best. While northward, coverage shifts to the east hugging the
Divide. Dry boundary layer conditions still whittle confidence away
on wetting rain. This will keep gusty outflow winds in the picture,
much like we saw last evening across the Grand Valley when 40 mph
winds worked westward out of some showers on the Grand Mesa.

Wind will continue to move wildfire smoke around. Erratic outflows
could push smoke into areas previously out of the downstream path.
Our hot and dry air mass will keep temperatures consistent with
yesterday, with area temperatures in excess of 5 degrees above
average. This trend continues for Tuesday, as we hold on to warm
conditions across the southern half of the U.S. Mostly zonal flow on
Tuesday will send additional shortwaves across the region, likely
shifting winds around, as well as providing additional orographic
shower enhancement. Ensemble PWATS jump about 20 percent in value
Tuesday, so expect to see additional terrain based storms and
showers. Some cloud cover could take a bite out of a few afternoon
highs too, but don`t bet on it.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 357 PM MDT Sun Jul 13 2025

High pressure will continue to support hot and dry conditions,
with increased PoPs in the afternoon. The coverage of showers
and thunderstorms vary each day as weak moisture advection
elevates PWAT anomalies in different parts of our CWA.
Unsurprisingly, the greatest chances for precipitation tend to
be over the high terrain. On Tuesday PWATs are near or below
normal, which may allow for convection over the high terrain,
including dry thunderstorms. On Wednesday shower and
thunderstorm coverage looks to increase as some moisture makes
its way into our region, particularly north of I-70. However, at
this point in time ensembles begin to differ on timing,
placement, and magnitude of moisture advection. The ECMWF Ens
favors stronger moisture advection later this week than the GFS
Ens, which puts maximum PWAT anomalies at above 150% of normal
and around 130% of normal, respectively. So, there is a chance
for a push of monsoon moisture later this week, but differences
in the guidance lowers confidence on this. High temperatures
remain 5 to 10 degrees above normal for the first few days of
the long term, but should begin decreasing towards normal as a
trough from the Pacific Northwest propagates eastward. Despite
dry weather, Red Flag conditions are expected to only be
localized at times as winds generally stay below critical fire
weather thresholds, with the exception of local areas.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 541 AM MDT Mon Jul 14 2025

VFR conditions begin the TAF period this morning with some
scattered upper level clouds hanging along the Divide and in the
San Juans. Winds will remain light this morning and afternoon
with a few terrain influenced gusts this afternoon. Showers and
thunderstorms develop on the terrain, favoring the San Juans and
adjacent to the Divide north of there. Erratic and gusty
outflow winds and lightning will pose the main threat to
aviators this afternoon. Ceilings will likely not reach
breakpoint conditions thanks to high based showers. Some cloud
cover will stick around the mountains tonight, but thin out
after midnight and terminals should finish up this TAF period
under VFR conditions again.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...LTB
LONG TERM...GF
AVIATION...TGJT