111
FXUS65 KSLC 251123
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
523 AM MDT Fri Sep 25 2026

.KEY MESSAGES, Issued 1034 PM MDT Thu Sep 24 2026...


- Isolated to widely scattered convection across southern and
  central Utah Friday.

- An approaching trough will bring cooler temperatures and 50%
  chance for widespread precipitation Sunday-Tuesday, with
  tropical moisture potentially leading to locally significant
  amounts.

&&

.DISCUSSION, Issued 1034 PM MDT Thu Sep 24 2026...
Weak, diffuse low pressure is in place this evening
across AZ and extending into UT and eastern CO. This, combined
with PWATs near 0.7 inches allowed isolated to widely scattered
weak convection to develop over mainly the southern Utah mountains
this afternoon which have now mostly dissipated, leaving some mid
and high clouds in place that will continue over much of southern
and eastern Utah into Friday morning.

An upper trough currently noted off the PacNW coast will make its
way inland tonight, crossing ID Friday before ejecting across
western MT. Ahead of this trough, isolated to widely scattered
convection can be expected once again Friday afternoon. These are
expected to develop over the southern and central Utah mountains,
then shift into the adjacent eastern valleys with the flow aloft
turning more westerly. A shallow cold front will push into
northwest Utah Friday night, bringing slightly cooler temperatures
to that area through Saturday.

With generally dry and stable conditions expected on Saturday,
attention then turns to the next trough, which will be deepening
off the West Coast on Sunday. Ahead of this trough, a vort max
originating near Hurricane Odalys in the eastern Pacific is
progged to lift into Utah Sunday afternoon, bringing an increase
in moisture and some widely scattered convection. The trough
itself is progged to approach Utah by Monday. Latest deterministic
EC/GFS and an increasing number of global ensemble members are
trending towards a splitting, closed-low evolution, which would
bring the system farther south with a slower eastward progression.
This would result in the system being able to better tap moisture
from Hurricanes Odalys and Polo, with longer duration
precipitation potentially aiding greater amounts. Widespread
precipitation appears likely across southern and eastern Utah, but
at this time, quite a bit of uncertainty remains with regards to
precipitation amounts, with a large spread in the NBM 25th-75th
percentile amounts. For example, many southeast Utah valley areas
have 48-hr totals Monday through Tuesday of 0.10 inches or less at
the 25th percentile but around 1 inch or more at the 75th
percentile. However, even with the uncertainty, the amounts at the
higher end of the probabilistic spectrum have been climbing,
meaning increasingly greater amounts are becoming possible.

Besides precipitation, the trough will bring cooler temperatures
into the area, with afternoon maxes falling 5-10 degrees below
normal for Monday and Tuesday, with many valleys reaching low 70s
at best. Temperatures will slowly rebound midweek as the storm
system exits the area, but significant spread exists in the large
scale pattern for the second half of next week.



&&

.AVIATION...

KSLC...The SLC terminal will see VFR conditions throughout the day
with increasing high clouds. Southerly winds are expected to shift
to the northwest between 20Z and 22Z, with a 30 percent chance this
shift will occur later than expected or not at all.

REST OF UTAH AND SOUTHWEST WYOMING...The airspace will see VFR
conditions throughout the day with increasing high clouds for
eastern portions of the area. Isolated showers and thunderstorms
will again develop over the higher terrain of southern Utah this
afternoon, bringing a low chance of gusty and erratic winds.
Elsewhere, dry conditions will prevail with increasing winds out of
the south.

&&

.FIRE WEATHER, Issued 444 AM MDT Fri Sep 25 2026...
Conditions will stay generally dry and seasonable
across Utah through much of the weekend, though the higher terrain
of southern Utah will see some isolated showers this afternoon
into the early evening. Southerly winds will pick up over the
weekend ahead of a Pacific trough expected to move through the
area Monday into Tuesday. The passage of the storm system will
bring the potential for more widespread precipitation,
particularly if it interacts with tropical moisture. Drier
conditions are then expected to return for much of the remainder
of the upcoming week.

&&

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

$$

PUBLIC...Cheng
AVIATION...Traphagan
FIRE WEATHER...Traphagan

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