342
FXUS65 KSLC 280953
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
353 AM MDT Fri Jun 28 2024

.SYNOPSIS...Much drier conditions can be expected areawide today,
though a few afternoon showers and storms will develop over
eastern Utah. High pressure will bring the return of hot and dry
conditions over the weekend. Increasing winds will bring the
potential for critical fire weather conditions. Moisture and
instability may return to the area early next week.

&&

.SHORT TERM (Through 12Z/6AM Sunday)...The Pacific Northwest
trough that grazed northern Utah yesterday is centered over
Montana this morning, putting Utah and southwest Wyoming under a
zonal flow aloft. Yesterday`s strong to severe convection
lingered into the overnight hours, but what remains has dissipated
or moved into western Colorado. In the wake of the trough, will
see some modest cooling, with maxes over northern portions of the
forecast area running close to normal for this time of year. What
may be more noticeable, however, is the dry air rapidly advecting
into the area from the west. By this afternoon anticipating PWs of
0.5 inch or less over all but far eastern Utah, the only area to
see any threat of convection this afternoon.

As the trough continues away from the area, the ridge over the
Great Basin will move over Utah for Saturday. A hot airmass will
rapidly advect in with highs over northern Utah running up to 10F
hotter than Friday. Occasionally breezy southwest winds could
combine with the dry airmass to produce critical fire weather
conditions over southwest Utah Friday into Saturday. See the Fire
Weather section of the AFD for more details.

.LONG TERM (After 12Z/6AM Sunday)...An approaching PNW trough will
increase southwesterly flow aloft. A well mixed boundary layer
during the day on Sunday will increase surface southwesterlies with
widespread gusts 25-35 mph. High pressure centered over Texas will
advect higher moisture into the southeastern portion of the CWA with
drier air encompassing the remainder of the region. This will pose a
fire weather risk Sunday afternoon. An isolated high based
thunderstorm will be possible across the southeastern portions of
the CWA. With inverted V sounding profiles, any storms that do form
will be capable of producing gusty microburst winds. Temperatures
will be in the mid to upper 90s for most locations with 100-107
across far southern Utah.

The aforementioned trough will move through Utah on Monday with
increasingly southwesterly flow and low RH once again. A dry cold
front will sweep through northern Utah, dropping high temperatures
~10 degrees compared to Sunday. This cooler air likely won`t make it
too far into central or southern Utah, resulting in little change in
daytime highs. Moisture will stay more elevated across southeastern
Utah so another isolated storm can`t be ruled out as this trough
moves by. A gradual transition to a dry northwesterly flow aloft
will scour out moisture across southeastern Utah and eliminate
almost all chances for precipitation for the remainder of the
period. Cooler air aloft across the northern CWA will keep
temperatures near normal with temperatures running ~5 degrees warmer
than normal across central and southern Utah.

By the end of next week the ensemble members signal a bit of
uncertainty regarding the overall synoptic pattern. 56% of members
have high pressure building off the PNW coast with a continued dry
northwesterly flow that will prevent temperatures from getting too
much above normal. 25% of the members have high pressure building
over the Great Basin that would keep conditions dry with hotter
temperatures. The remaining 19% of members have high pressure
centered to our southeast that could advect moisture into the region
indicative of a monsoon type of pattern.

&&

.AVIATION...KSLC...VFR conditions will persist for the KSLC terminal
through the long term period. Drier air moving into the region will
keep skies clear with light northerly winds transitioning to a brief
southerly flow before sunrise before going back to a light northerly
during the day.

.REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions will prevail
for the airspace. Dry air moving into the region will keep skies
mostly clear with increasing southwesterly winds during the day
across southern Utah and a lighter northerly wind across the
north.

&&

.FIRE WEATHER...Showers and thunderstorms that have lingered
overnight are diminishing and moving out of the area. Drier air is
rapidly moving into Utah from the west, keeping most of the area
free from convection this afternoon. However, isolated showers and
thunderstorms are anticipated over far eastern Utah. Over western
Utah, relative humidities will dip below critical levels, with
winds becoming strong enough over southwest Utah to support
isolated critical fire weather conditions. By Saturday, minimum
relative humidity values are expected to drop to or below 15
percent over much of Utah, with breezy winds anticipated over a
large portions of southwest and west central Utah. With winds
expected to increase areawide as the airmass over Utah continues
to dry, critical fire weather conditions could become relatively
widespread. Moisture and instability are expected to return to the
area beginning Monday.

&&

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

$$

SHORT TERM/FIRE WEATHER...Traphagan
LONG TERM/AVIATION...Mahan

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