Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 261142
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
542 AM MDT Tue Mar 26 2024

.KEY MESSAGES...

- A disturbance moves through today bringing another round of
  rain and snow showers. Expect 2 to 4 inches of new snow for
  the mountains with local amounts reaching near 6 inches
  possible by Wednesday morning.

- Below normal temps start to warm up Wednesday onwards as high
  pressure builds in. A return to above normal temperatures
  Friday and Saturday.

- Unsettled weather potentially returns late this weekend into
  early next week.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 333 AM MDT Tue Mar 26 2024

Light showers are tracking across the northern and central
portions of western Colorado and northeast Utah early this
morning as a weak shortwave passes. Showers are a bit further
south than models indicated with radar showing returns as far
south as Montrose and portions of the San Juans, but even some
light snow is reaching the valley floors of Vernal, Craig,
Hayden and Meeker. Trace amounts are expected in the valleys and
these showers appear brief as these showers are moving through
rather swiftly. Could also see a couple inches in the northwest
Colorado mountains out of this weak shortwave. Shower activity
becomes more widespread this afternoon as a stronger shortwave
follows with steep lapse rates upwards of 8 to 9 C/km and CAPE
values in the 150 to 250 J/kg range, especially across the
south/Four Corners. With lack of dynamic forcing, these showers
today will be instability and orographically driven and very
convective in nature. Anticipating another 2 to 4 inches of snow
in the mountains with the shower activity today produced by this
stronger shortwave, with favorable orographic northwest flow
possibly generating up to 6 inches in the higher elevations of
the Park Range. Temperatures will be about 10 degrees below
normal (some areas as much as 15 degrees below normal) for late
March today, but still mild enough to keep roads mostly wet
during the afternoon when much of this activity will fall.
Precipitation will be on and off again as well given the
scattered convective nature, so with the milder road
temperatures and high March sun angle, impacts will be limited.
Therefore, opted not to issue any Winter Weather highlights for
this activity today but some areas could see a burst or two with
locally higher amounts, so something to keep an eye on.

Northwest flow will keep some light orographic snow going in the
northwest Colorado mountains through Wednesday morning before
the ridge of high pressure slides in behind this departing
shortwave and upper level trough that has been bringing
unsettled weather since last week. One would think that high
pressure would bring a return to mostly sunny skies, but that is
not the case as another low pressure trough moves into the
Pacific Northwest, allowing the moisture to continue to
infiltrate the ridge. So sunshine will be filtered Wednesday
behind some high cloud cover. Overall, conditions are expected
to be dry with not much in the way of precipitation aside from
the lingering light snow over the northern divide mountains
possibly through early Wednesday afternoon. Wednesday will begin
our warming trend though as highs bump up a few degrees to sit 5
to 10 degrees below normal.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 333 AM MDT Tue Mar 26 2024

The low pressure system will sit just off the Pacific Northwest
coast Wednesday night into Thursday as quiet and dry weather
occurs over the Western Slope. The ridge of high pressure will
slowly slide eastward, giving us increasing southwest flow
Thursday afternoon. A leading shortwave will eject out ahead of
this low and across the northern tier of our CWA Thursday
evening into Friday, with scattered showers developing.
Meanwhile, the low off the Pacific Northwest coast is projected
to slowly drop down the west coast Thursday night into Friday
with a stronger closed low developing in the base of the trough
as it settles off the California coastline and tracks into SoCal
by Saturday. Scattered showers look to continue across northeast
Utah and northwest Colorado through Saturday while the rest of
the CWA will see southwest flow bring strong WAA into the area.
Conditions remain dry with the exception of the northern tier
but with this WAA, we will see highs rise to near normal on
Thursday, 5 degrees above normal Friday and 5 to 10 degrees
above normal by Saturday. This will raise snow levels and push
some of this colder air out, so highs in the lower elevations
will be well into the 60s and even pushing low to mid 70s for
the lower desert valleys of southeast Utah with near 70 for the
Grand Valley and Moab by Saturday. You would be correct if you
said that we have seen this before...last week in fact. All eyes
will be on this looming storm system off the California coast
and how it impacts our region when it eventually tracks inland.

Speaking of the next storm system, there is still lots of
uncertainty between models and between model runs. There are
some discrepancies with the timing, whether it will begin to
impact the area on Easter Sunday or starting early next week.
The latest projections have this system tracking inland across
the Desert Southwest Saturday into Sunday and across the Great
Basin and Western Slope Sunday into early next week. At the very
least, we can anticipate unsettled conditions returning late
this weekend into early next week with increasing chances and
coverage of precipitation. Time will tell how much precipitation
and where but right now with the southwest origins, this system
is looking warmer with not a whole lot of cold air. Mountains
will still see snow, but the snow levels look to be higher so
lower valleys will have a better chance of seeing rain. Lots of
details to hone in on as we get closer, but it is worth keeping
on the radar and in the back of your mind as we approach Easter
weekend and transition out of March and into April.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 542 AM MDT Tue Mar 26 2024

Light showers continue to move across portions of western
Colorado with VCSH and reduced CIGS/VSBY in light snow showers
mainly at the higher elevation and northwest Colorado valley TAF
sites. Showers will redevelop this afternoon, scattered to
widespread in coverage with VCSH and breezy afternoon winds at
most TAF sites. Isolated thunderstorms are also possible but
confidence too low to include in TAF. Expect below ILS CIGS
along the divide as well as in any showers with locally IFR
conditions. Areas outside of showers should see VFR to MVFR
conditions. BKN to OVC skies through the afternoon become more
SCT this evening from the west as this system exits stage right.
Lingering low CIGS and showers over the northern divide through
Wednesday morning.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...MDA
LONG TERM...MMS/MDA
AVIATION...MDA


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