737
FXUS65 KGJT 191157
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
557 AM MDT Sat Apr 19 2025

.KEY MESSAGES...

- Mountain snow continues through this afternoon, with
  additional accumulations of 3 to 8 inches expected, favoring
  the southwest Colorado Mountains, where Winter Weather
  Advisories continue.

- Freezing temperatures will impact susceptible vegetation in
  our low elevation valleys this morning and Sunday morning.

- Temperatures rebound next week with a warm up expected behind
  the Spring snow to the tune of 5 to 10 degrees above normal.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 420 AM MDT Sat Apr 19 2025

A closed area of low pressure continues to dive southward into
east-central Arizona and northwest New Mexico at this time,
resulting in much of the energy and lift to be taken further
south and east. Currently, it appears the San Juan mountains and
West Elks and Sawatch ranges are favoring from this enhanced
lift with snow continuing there and infrared satellite imagery
indicating some gravity waves pushing through that area. We`ve
seen a noticeable drop off in precipitation rates and
occurrence though across southeast Utah and areas along and
north of I-70. Therefore, decided to cancel the Winter Weather
Advisory for the La Sals and Abajos as rates and accumulations
have tapered off since last evening. The Gore and Elk Mountains
and Vail Pass area seems to be shadowed in this southwest flow
and rates have really dropped off there so the focus for the
next 12 hours or so appears to be the southwest Colorado
mountains and southwest facing slopes up the central divide for
an additional 4 to 8 inches of snow. As a result of clearing
skies across northeast Utah and northwest Colorado, efficient
radiational cooling has led to temperatures dropping well below
freezing this morning. There is still enough cloud cover over
the southern and central areas that temperatures haven`t dropped
quite as low but are hanging right around freezing or a little
above. Decided to add the Uinta Basin (UTZ024) and Debeque to
Silt Corridor (COZ007) to the Freeze Warning in effect through 9
am MDT this morning as the latest GDD (Growing Degree Days)
indicates that a good portion of these zones are above 50 GDD
and with the recent warmup this past week, vegetation would
appear susceptible.

This afternoon, roads likely will become wet but conditions
should start improving by late afternoon into the evening as
this trough exits the region. We will see a switch to northerly
flow this evening and as a result, lose the dynamic forcing
associated with the low as it moves into eastern New Mexico and
the Texas Panhandle. Skies are expected to clear area wide for
efficient radiational cooling and freezing temperatures looking
more likely. Therefore, upgraded the Freeze Watch for tonight
through Sunday morning to a Freeze Warning and added the Uinta
Basin and Debeque to Silt Corridor zones to it based on recent
GDD. While the freeze warning is only for areas where vegetation
is susceptible, other areas will see below freezing temperatures
so protect sensitive vegetation if you have any. Most areas will
be mostly sunny on Easter Sunday, except for areas north of I-70
where a weak shortwave may generate some light showers over the
northern mountains but chances are pretty low. Temperatures by
Sunday afternoon will warm up about 5 to 10 more degrees
compared to today, which should be milder than yesterday, and
end up closer to normal if not slightly below normal.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 420 AM MDT Sat Apr 19 2025

By Sunday night, today`s system will be well into the Plains,
and any mountain showers that formed during the afternoon will
taper off. Transient ridging passing through will lead to clear
skies and efficient radiational cooling, leading to another
round of potential freezes by Monday morning. Locations with
vegetation susceptible to the cold should keep a close eye on
the forecast and be ready to take measures to protect sensitive
plants and outdoor plumbing. Temperatures rebound to 5-10
degrees above normal on Monday, and stay there through mid week,
with desert valleys in the mid to upper 70s and mountain towns
in the upper 40s to low 50s. Moisture will remain trapped across
the region, leading to several days of isolated to widely
scattered mountain showers and thunderstorms. A system tracking
across the Northern Rockies Monday afternoon will just clip
northeastern Utah and northwestern Colorado, driving a more
widespread round of showers and thunderstorms over the higher
terrain. This system is a quick mover, expected to eject into
the Northern Plains Monday evening. So between the loss of
forcing and the loss of daytime heating, afternoon showers and
storms will taper after sunset. Elsewhere, skies are expected to
remain mostly clear.

After a period of near zonal flow and fairly quiescent
conditions on Tuesday, a trough moving into the West Coast will
turn flow southwesterly over the Desert Southwest. This will
drive temperatures up a few more degrees, with highs for the
back half of the week running 10-15 degrees above normal. This
first wave is expected to weaken as it tracks over the Northern
Rockies, bringing increased shower coverage and enhanced winds
as it tracks to our north. The next system to approach the West
Coast is looking stronger, and will bring some strong, gusty
southwest winds for the late week period as the pressure
gradient ahead of this low tightens up. This means a potential
return to elevated fire weather conditions to close out the
coming week.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 557 AM MDT Sat Apr 19 2025

Southern and central areas will continue to be impacted by snow
showers with MVFR to IFR conditions and ILS breakpoints being
reached through 16Z. Snow then becomes more scattered and
convective favoring the high terrain after 18Z with ILS
conditions at times at KTEX, KDRO and KGUC with the rest of the
area returning to VFR/MVFR conditions. Winds will be gusty at
times from the northwest this afternoon with improving
conditions and VFR by evening under clearing skies.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Freeze Warning until 9 AM MDT this morning for COZ006-007-011-
     020>022.
     Freeze Warning from midnight tonight to 9 AM MDT Sunday for
     COZ006-007-011-020>022.
     Winter Weather Advisory until 6 PM MDT this evening for COZ012-
     018-019.
     Winter Weather Advisory until noon MDT today for COZ017.
UT...Freeze Warning until 9 AM MDT this morning for UTZ024.
     Freeze Warning from midnight tonight to 9 AM MDT Sunday for
     UTZ022-024.

&&

$$

SHORT TERM...MDA
LONG TERM...BGB
AVIATION...TGJT