341
FXUS65 KSLC 152356
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
556 PM MDT Sat Aug 15 2026

.KEY MESSAGES, Issued 1239 PM MDT Sat Aug 15 2026...


- Isolated thunderstorms are expected across southwestern and
  northeastern Utah this afternoon and evening. Locally heavy rain
  will be possible with any thunderstorms across southwestern
  Utah, though the flash flood threat is lower than prior days.

- Elevated to locally critical fire weather conditions will occur
  across central and southern Utah Tuesday into Wednesday.

&&

.DISCUSSION, Issued 1239 PM MDT Sat Aug 15 2026...
Drier air continues to filter into the region under
fairly weak southwesterly flow, resulting in quieter conditions
this weekend across Utah and southwest Wyoming. Still, rainfall
over the past few days has resulted in a relatively moist boundary
layer, with dewpoints this morning still in the 50s across many
areas. With this low-level moisture, isolated showers and
thunderstorms will redevelop this afternoon, primarily over higher
terrain and over far southwestern Utah. The flash flood threat is
much lower today as the air mass trends drier, but a Flash Flood
Potential Rating of Possible is still in place today for Zion and
Snow Canyon given slow storm motions and this lingering low-level
moisture.

While a ridge across the Southern Plains will still be the main
large-scale feature in our forecast, a shortwave trough moving
through the Interior Northwest on Tuesday into Wednesday could act
to enhance southwesterly flow and draw moisture/thunderstorm
chances across northern Utah, particularly on Tuesday afternoon.
Forecast uncertainty increases thereafter, though model guidance
does favor high pressure strengthening once again over the Four
Corners region, which could bring back monsoonal moisture as early
as Wednesday (but likely Thursday or later). With strengthening
high pressure, temperatures will also slowly increase back to
around normal by mid-week.



&&

.AVIATION...KSLC...South winds are gradually moving back into the
terminal at 00z and will likely prevail through the night into
tomorrow morning before turning northwest around 19z tomorrow.
However, there is a 40% chance that light northwest winds will make
a brief return through 02z this evening. VFR conditions will prevail
through the valid TAF period. There is a 10% chance of a rain shower
at the terminal tomorrow afternoon.

REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions will prevail
areawide through the valid TAF period. Isolated showers and
thunderstorms are expected to dwindle tonight, then redevelop again
tomorrow afternoon. Generally light winds with typical diurnal
trends are expected at area terminals.

&&

.FIRE WEATHER, Issued 128 PM MDT Sat Aug 15 2026...
A drier air mass will continue to shift into the
region, with humidities expected to decrease through at least
mid-week statewide. Valley RH will reach critical levels as early
as Sunday, becoming more widespread heading into the work week.
Overnight RH recoveries will become increasingly poor through at
least Wednesday morning, with many valleys only reaching 30-45%. A
system moving through the Interior Northwest will bring an
increasing threat of gusty winds...with elevated to locally
critical fire weather conditions Tuesday and Wednesday across
primarily central and southern Utah. Isolated thunderstorms are
possible today and Sunday afternoon mainly across higher terrain,
with otherwise little to no wetting rain chances.

&&

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

$$

PUBLIC...Cunningham
AVIATION...Cheng
FIRE WEATHER...Cunningham

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