121
FXUS65 KSLC 121121
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
520 AM MDT Sat Sep 12 2026

.KEY MESSAGES, Issued 1009 PM MDT Fri Sep 11 2026...


- A marginal risk (level 1/4) for excessive rainfall is in place
  across portions of southern Utah through Tuesday.

- Gusty winds up to 45 mph will develop across portions of
  northern Utah Saturday night into early Sunday morning. Wind
  gusts to 40 mph will continue behind the cold front through
  Sunday evening.

&&

.DISCUSSION, Issued 225 PM MDT Fri Sep 11 2026...
While an increase in moisture is noted across the central and
southern portions of Utah this afternoon, the coverage of showers
and thunderstorms is rather dismal as originally anticipated. That
said, it is evident that the environment is conducive to
thunderstorms and heavy rainfall as SPC mesoanalysis suggests
upwards of 1500-2000J/kg of CAPE paired with PWAT values around 1
inch in southern Utah. One singular storm moving across the
southern area has been able to tap into this instability and
maintain itself while the remainder of the thunderstorm activity
has been rather short-lived. In any case, moisture has positioned
itself in place across the southern half of Utah and will continue
to increase subtly over the next couple of days.

Coverage of showers and thunderstorms is anticipated to be just as
isolated on Saturday as weak subsidence in the wake of the current
shortwave inhibits widespread thunderstorm activity. The more
noteworthy widespread weather that Saturday will feature will be
an increase in southwest winds across much of the region, with the
strongest winds targeting west-central and southwest Utah, as well
as southwest Wyoming. In these areas, afternoon wind gusts will
reach upwards of 30-35 mph as a trough remains over the PacNW
region. This trough is slated to progress inland and graze
northern Utah through the second half of Sunday and into Monday
morning, introducing a cold front to the northern area. Behind the
cold front, a brief period of stronger west to northwest winds can
be expected in northern Utah on the lee sides of mountain ranges.

Cooler temperatures are expected in the wake of the cold front on
Monday across the northern area, with warm southerly return flow
bringing a gradual warming trend into the middle of the week. For
southern Utah, some level of moisture will remain in place from
now through next week, bringing at least a chance for showers and
thunderstorms each afternoon.





&&

.AVIATION...

KSLC...Generally non-impactful weather expected to persist through
the TAF period. VFR conditions will prevail with isolated cloud
cover above 10 kft or so. Winds will follow a diurnally typical
direction pattern, shifting to the NW around 18-20Z Saturday, and
back to SE around 02-04Z Sunday. Southerly winds will then likely
increase through Sunday morning ahead of an approaching system.

REST OF UTAH AND SOUTHWEST WYOMING...Isolated showers and
thunderstorms will be possible for southern and eastern Utah
terminals Saturday afternoon. Otherwise, VFR conditions are expected
to prevail with a mix of mid to upper level clouds filtering
through. Winds will tend to follow a diurnally typical pattern, with
south to southwesterly winds beginning to increase near sunrise
Sunday morning ahead of an approaching system.


&&

.FIRE WEATHER, Issued 207 AM MDT Sat Sep 12 2026...
Sufficient moisture will linger across portions of
southern and eastern Utah, resulting in isolated showers and
thunderstorms primarily during the daytime hours. A stronger
approaching system will bring gusty conditions, generally from the
south to southwest into Sunday. A largely dry associated cold
frontal boundary will be pushed southward through Utah roughly
late Sunday into the daytime Monday. Following this frontal
passage, winds will generally shift north to northwest, with a
period of gusty winds also likely to accompany it. This will be
especially true for the lee sides of northern Utah mountain ranges
and terrain features. Cooler temperatures will follow the front,
with the more pronounced temperature drops noted across the
northern half of Utah. Temperatures will then gradually trend
upwards throughout the upcoming week. Humidity overall will remain
fairly low with daytime minimum values in valley locations likely
falling into the teens. That said, enough moisture will linger to
allow isolated high based shower and thunderstorm chances across
portions of southern and eastern Utah, primarily during the day,
through the upcoming week.

&&

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

$$

PUBLIC...
AVIATION...Warthen
FIRE WEATHER...Warthen

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