759
FXUS65 KGJT 070956
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
356 AM MDT Tue Oct 7 2025

.KEY MESSAGES...

- A Freeze Warning is in place for the Yampa and White River
  Basins through 10 am this morning.

- Isolated showers and thunderstorms possible over the San Juan
  Mountains today and Wednesday.

- Drier conditions continue through Wednesday. However, moisture
  returns Thursday through the weekend, bringing the potential
  for widespread precipitation.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 356 AM MDT Tue Oct 7 2025

Skies are mostly clear across the region as the shortwave trough
exits to the Front Range this morning and high pressure builds
in from the southeast. Efficient radiational cooling is taking
place leading to near to below freezing temperatures in the
northwest Colorado valleys where a Freeze Warning remains in
effect through 10 am this morning. This appears on track as
Craig has already dipped into the upper 20s while the rest of
the valleys remain above freezing. Weak moisture working around
the high will allow for some isolated showers and storms to
sneak into the southeastern portion of the San Juans and
southern valleys late this afternoon and evening, although
chance of wetting rain is low. Otherwise, skies will remain
mostly sunny today for much of the region with dry conditions
and temperatures bumping up a bit closer to normal. By
Wednesday, the pattern remains relatively unchanged with
moisture continuing to sneak into southwest Colorado resulting
in some isolated showers and storms mainly over the San Juans.
The gradient will increase a bit as a low pressure trough drops
into the Pacific Northwest and Hurricane Priscilla moves further
north up the Baja Peninsula coastline, allowing the high
pressure over Texas to nudge a bit closer. This will allow a
subtropical jet to set up over the Great Basin, resulting in
some breezier conditions Wednesday afternoon and high
temperatures rising to around 5 to 10 degrees above normal.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 356 AM MDT Tue Oct 7 2025

The main player of the forecast is a surge of tropical moisture
that arrives to the Four Corners region late Wednesday into
Thursday courtesy of Hurricane Priscilla. With a ridge of high
pressure promoting a steady stream of southwesterly flow across
eastern Utah and western Colorado, a healthy tap of tropical
moisture is very likely through at least Sunday. If the 07.00
ECMWF Ens has it`s way, it could remain soggy well into next
week.

The peak of the heavy rain threat currently looks to be Friday
and Saturday when PWATs surge over four standard deviations
above normal. Abundant cloudiness from all of this moisture will
likely lead to efficient stratiform rains with embedded storms
in the afternoons, but if clear patches develop during peak
daytime heating, thunderstorms will be capable of producing very
heavy rain and flash flooding. We`ll also have to keep an eye
on the potential for jet dynamics or pulses of positive
vorticity advection during this timeframe as the additional
synoptic forcing would increase the potential for flash flooding
as well. There are still a lot of variables to iron out as this
system approaches, but a prolonged period of wet weather is all
but guaranteed.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1133 PM MDT Mon Oct 6 2025

VFR conditions are forecast through the TAF period with light,
terrain-driven winds.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Freeze Warning until 10 AM MDT this morning for COZ002.
UT...None.

&&

$$

SHORT TERM...MDA
LONG TERM...KAA
AVIATION...TGJT