758
FXUS65 KGJT 292040
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
240 PM MDT Fri Aug 29 2025

.KEY MESSAGES...

- Showers and thunderstorms expected this afternoon, tapering
  off this evening.

- Temperatures trend nearly 10 degrees below normal today.

- Warmer and drier conditions develop this weekend with some
  terrain based showers in the forecast.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 135 PM MDT Fri Aug 29 2025

A shortwave trough is currently progressing eastward over the
forecast area, and is associated with an expansive shield of
stratiform mainly north I-70. The wave did bring abundant moisture
so there are also scattered showers south of I-70. This is where
there are breaks in the clouds and perhaps pockets of instability.
Therefore thunderstorms will be possible for these locations this
afternoon and evening. The stronger cells may be capable of moderate
to heavy rainfall, which could lead to localized flooding. Cloud
cover and rain cooled air will keep temperatures well below normal
for most of the area. By midnight the wave crosses the Divide and
most of the showers dissipate. Any clearing tonight could result in
localized dense fog overnight especially where it rains today.
Tomorrow dry air continues to filter in from the northwest, but
there may be enough mositure for afternoon showers and storms over
high terrain near the Divide with a few possible further west near
the state line. Can rule out a brief down pour with these showers
given a little more instability compared to today.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 135 PM MDT Fri Aug 29 2025

On Sunday PWAT anomalies will fall to below normal across the CWA,
bringing an end to the brief return of the monsoon. Terrain based
afternoon convection is still in the forecast Sunday, but elevated
PoPs are primarily located over Colorado`s southern mountains where
PWAT anomalies are expected to be the greatest. Moisture will linger
in the southern mountains while the rest of the CWA remains dry,
leading to forecasts for afternoon convection on Monday and
Tuesday that look similar to Sunday`s. Some guidance suggests a weak
return of moisture as early as midweek, which would allow for
afternoon convection to become more widespread over the higher
terrain. However, there is little agreement between ensembles on the
timing of this moisture push. Temperatures begin to climb this
weekend, resulting in near normal high temperatures through the long
term.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1140 AM MDT Fri Aug 29 2025

Showers are moving through the area this afternoon. Isolated
thunderstorms may develop where the SCT to OVC cloud cover
clears a bit this afternoon. Brief periods of heavy rain and
gusty outflow winds are the primary concerns with thunderstorms.
After sunset most of the precipitation will have moved east of
the Divide. Showers and storms may briefly cause MVFR conditions
or a drop below ILS breakpoints. VFR conditions are expected to
prevail overnight.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...KJS
LONG TERM...GF
AVIATION...TGJT