752
FXUS65 KGJT 160002
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
602 PM MDT Wed Oct 15 2025

.KEY MESSAGES...

- Strong thunderstorms are possible in southwest/south central
  Colorado this evening.

- Flash flooding remains a concern for portions of Archuleta and
  Hinsdale counties this evening.

- The passing frontal boundary will bring freezing temperatures
  to low valleys Friday morning.

- The next system drops down from the northwest early next week
  bringing scattered rain and mountain snow showers to the
  region.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 336 PM MDT Wed Oct 15 2025

The persistent low pressure center camped out over the Great Basin
continues to deliver showers and thunderstorms to water logged
portions of Southwest Colorado this afternoon. Flash Flood
highlights remain in place for portions of Archuleta and Hinsdale
Counties, as well as for the San Juan River through Pagosa Springs.
The low lifts north and east out of the Great Basin this evening.
This will shift some of the training storm activity east across the
Divide out of the region by daybreak. In the meantime, a few strong
storms are not out of the question on the shoulders of the San Juans
this evening. Gusty winds, hail, and heavy rain are possible with a
few storms. This will be enough of a threat to hang on to flood
highlights until we can get enough dry air to squash precipitation
potential.

Tonight, closer to the low pressure center and along the trailing
frontal boundary, showers and a few isolated thunderstorms will
continue across the region north of the highway 50 corridor. Snow
levels drop to near 7000 feet by daybreak, this should deliver some
light snow mixed in with the rain by daybreak for most of our
mountains. The best chances for accumulating snowfall will be on the
higher terrain of our northern mountains, including the Uintas,
Elkheads, and Park Range, where 3 to 5 inches of snow are expected
above treeline. Between treeline and the lowest snow levels, a
dusting to 1 inch is expected. Precipitation will finally wind down
for most of the region on Thursday, with a few showers hanging on
along the departing frontal boundary north of the highway 40
corridor Thursday afternoon. Clear skies and cold air behind the
front will usher in a wave of some of the coolest temperatures of
the season Friday morning. Mountain lows will be in the 20`s, while
lower valleys should all reach the upper 30`s, including some below
freezing. A Freeze Watch is in place Thursday night and Friday
morning for many of our valley locations, where overnight lows will
dip into the upper 20`s.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 336 PM MDT Wed Oct 15 2025

On Friday the low pressure system impacting our CWA will be centered
over North Dakota, well to our northeast. After the passage of this
system, flow will shift to northwesterly, bringing drier air to
the region. In general, PWATs will fall to near or below normal
through the weekend, with the lowest amounts falling to around
50% of normal. This will keep us dry pretty much until the next
system arrives, perhaps early next week.

With cooler northwesterly flow in place, and reduced cloud cover
overnight from drier conditions, overnight lows will likely drop
below freezing for many high elevation locations, including mountain
valleys. The Grand Valley and desert valleys of eastern Utah look to
remain above freezing temperatures through the long term period.
Temperatures will warm a bit Saturday and Sunday as flow begins to
transition to westerly.

The next potential for a return of active weather looks to be early
next week. Models are showing a trough moving through the west as
early as Sunday evening, and potentially reaching our CWA Monday.
There is still some significant differences between models on the
timing and southward extent of the trough. Additionally, ensembles
are suggesting dry conditions at the start of next week, which would
lead to a lower precipitation event, even with abundant upper level
support. So, confidence remains pretty low regarding the details of
this potential system.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 554 PM MDT Wed Oct 15 2025

Thunderstorms will continue across portions of southwest
Colorado with scattered showers across the northern and central
areas this evening with showers continuing overnight across
northwest Colorado as a low pressure system passes through.
Coverage of showers is scattered so confidence in occurrence at
TAF sites is lower so included PROB30 groups to account for
these showers/storms through Thursday morning. Expect generally
VFR conditions with periods of MVFR during any showers. The
heavier showers are focused across southeast portions of the CWA
which do not appear to impact TAF sites. Drier air will
accompany the frontal passage overnight into Thursday, further
reducing shower coverage. Expect breezy to windy conditions of
25 to 35 kts to TAF sites this evening into portions of the
overnight as this system passes through.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Freeze Watch from late Thursday night through Friday morning
     for COZ001-002-005-007-008-020>023.
UT...None.

&&

$$

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