Area Forecast Discussion Issued by NWS Salt Lake City, UT
000
FXUS65 KSLC 102150
AFDSLC
Area Forecast Discussion
National Weather Service Salt Lake City UT
350 PM MDT Wed Apr 10 2024
.SYNOPSIS...High pressure building into the area will result in a
drying and warming trend which will continue through the remainder
of the week. A weak wave may bring some high-based convection to
the area on Friday, followed by another storm system arriving late
in the weekend.
&&
.SHORT TERM (THROUGH 12Z FRIDAY)...An upper level ridge over the
West Coast this afternoon will continue to shift eastward tonight
into tomorrow, becoming centered over Utah tomorrow afternoon. A dry
and stable northwesterly flow aloft will remain in place over Utah
tonight as a result, then turn more southwesterly late tomorrow as
the ridge axis shifts east.
Just a few shallow cumulus clouds are noted on satellite imagery
this afternoon, mainly over northern and central Utah, but these
should diminish tonight with the loss of daytime heating.
Temperatures will continue trending warmer tomorrow by another 5-10
degrees, allowing most Utah valleys to reach into the upper 60s to
low 70s for afternoon maxes (upper 70s to low 80s across the far
south).
.LONG TERM (After 12Z Friday)...Ridging overhead on Friday will
result in dry southwesterly flow and warming aloft and at the
surface. Winds aloft throughout the day will mix down to the
surface, but given relatively light winds aloft gusts shouldn`t
reach advisory criteria (~<30 mph) with some slightly gustier winds
across the west desert. Ensemble mean H7 temperatures ~6C will
translate to surface temperatures 10-15 degrees above normal. A
shortwave will be traversing across the Great Basin Friday afternoon
which will result in isolated (~20% chance) high based convection,
primarily to our northwest. Given inverted V model soundings, there
is potential for microbursts with any convection that does develop.
Heading into the weekend a cutoff low will be making its way onto
the central California coast. However, timing with these cutoff lows
tend to be tricky, particularly the last several that have impacted
our CWA. The trend has been for them to slow down, compared to what
models suggest. The exact timing of this cutoff low to move into the
Great Basin will not only dictate precipitation chances for us, but
will also impact the following trough early next week. 60% of
guidance brings this low into the Great Basin by Sunday, while the
other 40% are slower with the arrival happening on Monday.
Regardless of the timing, the magnitude of the storm is fairly
minimal as it starts to weaken as it moves inland. This will result
in high pop/low QPF variety of showers on Sunday/Monday with the
biggest change coming in the form of increased cloud cover and
temperatures getting closer to normal for this time of year.
A deeper trough early next week has the potential to provide more in
the way of colder temperatures and greater QPF. However, as
mentioned previously, the track of this trough will be determined by
how quickly the cutoff low moves through the area. 68% of ensemble
members bring the trough through the Great Basin with H7
temperatures ~-12C (amongst the 25th percentile). This would likely
allow for snow down to valley floors. However, the other 32% of
members keep this trough to our north and east resulting in drier
and warmer weather (-5C; 75th percentile).
&&
.AVIATION...KSLC...Minimal operational concerns are forecast for the
KSLC terminal through the valid TAF period. Northwesterly winds will
prevail through the early evening, transitioning to a southerly flow
after 03Z. There is a 20% chance that winds remain northerly through
04Z.
.REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions are expected to
prevail across the forecast area through the valid TAF period under
largely clear skies. Any cumulus buildups over the terrain will
settle after sundown. Winds will be generally light and terrain
driven across much of the area, with any gusts (mainly in the KBCE
and KCDC area) subsiding after sundown.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Flash Flood Watch through Tuesday evening for UTZ125.
WY...None.
&&
$$
Cheng/Mahan/Webber
For more information from NOAA`s National Weather Service visit...
http://weather.gov/saltlakecity