152
FXUS65 KSLC 272144
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
344 PM MDT Thu Mar 27 2025

.SYNOPSIS...Unseasonably warm temperatures and breezy conditions
this afternoon, before the pattern shifts to a cooler, but more
seasonable, and wetter regime into next week.

&&

.SHORT TERM (Through 12Z/6AM Saturday)...
Key Messages:
* Near-record warmth and breezy conditions continue today through
  this evening, with some patch areas of blowing dust expected
  over western Utah.
* A cold front passage tonight brings a return to more seasonable
  temperatures starting Friday into the weekend, along with
  increased chances of valley rain and mountain snow showers.

This afternoon, breezy southwest winds have developed ahead of an
approaching cold front that will move through overnight tonight.
With a dry, well-mixed airmass in place temperatures have been
able to approach daily record values across the region. The deep
mixing is also helping to transfer high momentum air aloft to the
surface, especially across western Utah into the central Wasatch
Front. With around 40 knots of wind aloft, gusts to around 40 mph
are expected to continue across western Utah and southwest Wyoming
this afternoon, around around 30-35 mph into the Wasatch Front.
All of this remains below wind advisory levels (45 mph or higher
for 3 plus hours). That said, winds are still expected to be
sufficient to loft some areas of dust, mainly across western Utah.

The cold front will cross the region tonight, which will result
in a noticeable drop in winds behind the front across northern
Utah. Southwest winds will still remain in place across far
southern and eastern Utah through Friday, with breezy (gusts to
around 30-35 mph) expected to continue there. As the cold front
moves through northern Utah, moisture and forcing will be waning,
and thus the chance of measurable precipitation is only as high as
20-50% overnight from around the Salt Lake Valley northward to
the Idaho Border. With mild temperatures in place, this will be
valley rain and mountain snow.

On Friday, temperatures will run much cooler, and closer to
seasonal normals (20 degrees cooler than today across northern
Utah). Isolated to scattered showers will re-develop over and east
of the central spine of mountains by Friday afternoon, which is
also roughly along the stalled surface boundary. However, the
chance of measurable precipitation is largely less than 30
percent.

.LONG TERM (After 12Z/6AM Saturday)...
Main theme of the long-term portion of the forecast is unsettled
conditions. Kicking off the period on Saturday, model consensus
places an upstream trough axis just to our west. As a result,
widespread valley rain and mountain snow will be in place across
central and northern Utah as well as SW Wyoming for much of
Saturday. There remains some spread among the model distribution
regarding precipitation onset on Saturday, with onset ranging from
around sunrise to as late as late Saturday morning. Placement is
more certain, with showers developing along/near the Nevada border
into the northwest corner of Utah before spreading eastward. With
cold advection taking over in the afternoon after a passage of a
baroclinic zone/cold front, snow levels will fall through the day.
At the onset of precipitation, snow levels will range from
6kft-7kft, falling to 5.5kft to 6kft, suggesting the potential for
rain to end as snow or a mix of rain/snow on the highest benches.
Precipitation will wind down through the evening hours as a mid-
level shortwave ridge builds into the Great Basin. In terms of
precipitation, generally speaking, a few tenths of an inch to
0.30" of QPF falls within the 25-75th percentile, with 0.30"-0.80"
of QPF and 3-10" of snow, locally higher in the Upper
Cottonwoods.

By Sunday, a weak shortwave is forecast to propagate eastward across
southern Utah, resulting in a cluster of showers there, especially
during the afternoon/early evening. Otherwise dry conditions with
seasonable temperatures will be in place.

Monday, model suite is well-clustered around the idea of a broad,
seasonably strong area of low pressure forecast to be centered off
of the WA/OR coastline. This low is forecast to evolve into an open
trough as it advances eastward across the Intermountain West, with
some differences on the strength and timing of this evolution. As
the trough advances eastward, the pressure gradient will tighten
across Utah and SW Wyoming on Monday, bringing breezy conditions to
the area, with a broad swath of 35-45 mph southwest winds forecast
to develop, with the strongest winds currently forecast across
generally the southern half of Utah with emphasis across the western
valleys. Precipitation chances gradually increase late Monday across
the northern half of the area before gradually spreading southward
into Tuesday. There is a portion of the model suite that keeps
southern Utah dry, while the remainder of the distribution does
support some precipitation as we head towards the Arizona border. It
is certainly more likely that measurable precipitation will occur
across central/northern Utah and SW Wyoming, however. Spread in snow
level begins in the 6.5-7.5kft when precipitation onset begins late
Monday, falling to 4kt-5kft as we head into Tuesday, suggesting snow
levels falling to valley floors for northern valleys as we head
through Tuesday. At this point, it does appear like a borderline
Winter Weather Advisory type event for our northern mountains, with
a trace to 2" across northern valleys based on the current model
distribution. Significant model spread does begin to creep into the
forecast by Wednesday, when about half of the guidance keeps
unsettled conditions around through Wednesday, while the remainder
of the guidance is more progressive with a shortwave ridge building
into the area ahead of another trough. At this time, official
forecast is more in line with the unsettled model camp through the
middle and later portion of next week.

&&

.AVIATION...KSLC...Thick mid-level cloud deck has built into the
region and will remain in place through Friday. Gusty S-SW winds
will continue into the early evening hours. A wind shift to the NW is
expected between 04-06Z, with initial gustiness in the 20-25kt range
for about an hour following the wind shift. VCSH after 05Z as
showers develop over the nearby terrain. This will bring CIGs down
into the 6kft-10kft range overnight into Friday morning.

.REST OF UTAH AND SOUTHWEST WYOMING...Gusty S-SW flow will continue
into early evening before a wind shift to the NW builds into the NW
corner of the state between 7PM-8PM, before sliding southward across
the Wasatch Front between 9PM-11PM, with an initial surge of
gustiness for roughly an hour proceeding the frontal boundary. The
front will wash out across central Utah by late evening. Showers are
expected late evening through overnight near the Idaho border and
across the northern mountains, leading to some mountain
obscuration.

&&

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...None.
WY...None.
&&

$$

SHORT TERM...Church
LONG TERM...DeSmet
AVIATION...DeSmet

For more information from NOAA`s National Weather Service visit...
http://weather.gov/saltlakecity