223
FXUS65 KGJT 042356
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
456 PM MST Thu Dec 4 2025

.KEY MESSAGES...

- Two rounds of winter weather is on tap tonight through
  Saturday night favoring the northern and central Colorado
  mountains.

- The first round will mainly impact the northern Colorado
  mountains late this evening through tomorrow afternoon. A
  Winter Weather Advisory is in effect for the Elkhead and Park
  Mountains beginning at 11 PM.

- Round two arrives Friday night with more widespread
  accumulations and stronger winds at the high elevations.
  Winter Storm Warnings are in effect for portions of the
  northern and central Colorado mountains Friday evening through
  Saturday evening.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 416 PM MST Thu Dec 4 2025

Our next winter weather system arrives tonight as a shortwave
trough accompanied by an increase in moisture moves in from the
northwest. PWAT anomalies surge to 150% of normal with its
passage with enough lift to support light to moderate snowfall
rates mainly centered over the northern Divide mountains.
Impacts from this snowfall will be greatest over the Elkhead and
Park Mountains where a Winter Weather Advisory is in effect
from 11 PM this evening to 5 PM Friday. Hazardous travel is
likely over mountain passes during this timeframe from snow-
covered roads and reduced visibility. Use caution while driving!


Adjacent high valleys and other area mountain ranges along and
north of Interstate 70 will likely see an inch or two of light
snow over the next 24 hours. You may encounter winter driving
conditions, especially during periods of active snowfall. Drive
carefully!

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
Issued at 416 PM MST Thu Dec 4 2025

By Friday night heavier snow rates should begin in the northern
mountains. The onset of the heavier snowfall is associated with
a push of anomalous moisture into the region from the
northwest. PWATs 175 to 200% of normal are expected advect
across the CWA late Friday through much of Saturday. In addition
to the elevated atmospheric moisture, northwesterly flow will
support orographic lift, especially in our northern mountains,
and disturbances embedded in the flow will provide additional
upper level support. As the additional upper level support moves
through the area, beginning overnight Friday, the increased
snowfall rates will spread down the Divide. The GFS Ens and
ECMWF Ens seem to have good agreement run to run on timing and
amounts, and timing is similar between these ensembles, but
between the ensembles snowfall amounts still differ a bit.
Regardless, confidence is high enough to issue Winter Storm
Warnings for some of our northern and central mountain zones, in
addition to some Winter Weather Advisories as well. Presently,
the greatest snowfall rates are expected to occur late Friday
night through Saturday morning, but snowfall looks to continue
through Saturday night. Hazardous to dangerous travel is
possible during this event, so be sure to use caution if
traveling.

Drier air moves in on Sunday, which should end most snowfall.
However, orographic lift from persisting northwesterly flow may
allow for continuous light snowfall in the northern mountains.
Otherwise, generally quiet weather is in the forecast for the
start of next week. High temperatures will fluctuate around
normal through most of the weekend, but may warm towards the end
of the long term.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 453 PM MST Thu Dec 4 2025

Winter weather returns to the higher terrain tonight which will
bring increased coverage of lower clouds beginning this
evening. Chances for snow look to begin around 12Z for many
mountain sites. PROB30 has been included for sites where
confidence is highest, with HDN seeing a brunt of the snowfall
tomorrow. Southwest winds pick up tomorrow afternoon with snow
showers winding down at most terminals. This lull in sensible
weather will be short lived with another winter storm arriving
Friday night.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Winter Weather Advisory from 11 PM this evening to 5 PM MST
     Friday for COZ004.
     Winter Storm Warning from 5 PM Friday to 11 PM MST Saturday
     for COZ004-013.
     Winter Storm Watch from Saturday evening through Sunday
     morning for COZ004-010-013.
     Winter Weather Advisory from 5 PM Friday to 11 PM MST Saturday
     for COZ005.
     Winter Weather Advisory from 11 PM Friday to 11 PM MST
     Saturday for COZ008-009.
     Winter Storm Warning from 11 PM Friday to 11 PM MST Saturday
     for COZ010-012.
UT...None.

&&

$$

SHORT TERM...KAA
LONG TERM...GF
AVIATION...TGJT