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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS65 KGJT 021717
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1017 AM MST Tue Mar 2 2021

.SHORT TERM...(Today through Wednesday)
Issued at 525 AM MST Tue Mar 2 2021

Not a cloud in the sky early this morning as high pressure remains
in control. Expect plenty of sunshine today with temperatures
climbing to near seasonal norms after a chilly start. The mid-
level ridge responsible for our recent dry and sunny weather will
begin to break down and slowly slide eastward into the Plains
tonight into Wednesday. As this occurs, a closed mid-level low
will lift northeastward into southern California, which will
eventually bring our next opportunity for precipitation. Ahead of
this low, increasing southwest flow will usher in warmer air and
result in surface temperatures on Wednesday that are several
degrees higher than today. In fact, Grand Junction will have a
decent shot of recording its first 60-degree day of 2021. Clouds
and moisture will then be on the increase late in the day as the
mid-level closed low continues to trek northeast into the
southern Great Basin.

.LONG TERM...(Wednesday night through Monday)
Issued at 525 AM MST Tue Mar 2 2021

By Wednesday night, dynamical forcing associated with the closed
low will become quite strong as broad difluence coupled with the
left exit region of a 125kt upper jet will maximize lift over
eastern Utah and western Colorado. Numerous showers will develop
in response and gradually build north and east through the night
and into the day on Thursday. Given that there is no real cold air
source other than what is created dynamically under the cold pool
aloft, snow levels look high enough where precipitation in most
valleys should fall as either plain rain or perhaps a rain/snow
mix. Right now, rainfall amounts don`t look overly impressive and
will likely end up a quarter of an inch or less. That being said,
it`s been very, very dry the last couple of weeks so we`ll
certainly take what we can get.

In the mountains, particularly the San Juans, we`re likely
looking at an advisory level snow event with 6-12 inches in the
forecast. Still a bit early to issue any winter highlights with
this package however, and want later shifts to get a look at the
latest data before making any decisions. The central mountains
(and to a lesser extent the northern mountains) will likely get in
on the snow action as well, but snow amounts will be less there,
totaling 4-8 inches and 3-6 inches, respectively. With the closed
low crossing over the forecast area during the day on Thursday,
convection will definitely play a role and result in higher (or
even lower) amounts. Regardless, this storm system will be a quick
mover and expect most precipitation to wrap up from west to east
Thursday night.

In the storm`s wake, another large ridge builds into the Great
Basin Friday into Saturday. With any lingering clouds giving way
to mostly sunny skies on Friday, expect a quick return to
unseasonably mild temperatures. This will be even more noticeable
on Saturday, with widespread highs in the 50s for the higher
valleys, and 60s to near 70 in the lower and desert valleys. A
taste of spring for sure!

By Sunday, another piece of energy will likely slingshot from
California into eastern Utah and western Colorado, bringing
another potential shot of precipitation. However, continued to
lean on blended guidance given differences in amplitude and
timing of the wave. Either way, dry and mild weather likely
returns on Monday.

&&

.AVIATION...
-- Changed Discussion --
(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1016 AM MST Tue Mar 2 2021

Sunny skies continue as high pressure shifts eastward. No
aviation concerns noted. VFR for the next 24 hours.
-- End Changed Discussion --

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...None.
UT...None.
&&

$$

SHORT TERM...MDM
LONG TERM...MDM
AVIATION...TGR