875
FXUS65 KSLC 182103
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
303 PM MDT Mon Aug 18 2025

.SYNOPSIS...High pressure will bring a warming and drying trend
to the region through Tuesday. A monsoon surge will begin as early
as Wednesday and continue through at least next weekend.

&&

.SHORT TERM (Through 12Z/6AM Wednesday)...Mid level ridging
becoming established near the Four Corners area will become the
dominant weather feature throughout the forecast period. This will
bring a continued warming trend through Tuesday, as max
temperatures climb another 4-6F, and challenge daily records at a
few locations including KSLC (100F at KSLC set in 2020).

With this warming trend, HeatRisk continues to suggest an increase
in the threat of heat related illness, especially for those
without proper hydration or cooling. If your plans take you
outdoors over the next 3-4 days, consider avoiding the heat of the
day and make sure to drink plenty of water. With the increase in
moisture later in the week, uncertainty increases regarding the
duration of this event, and given several recent warm stretches of
similar intensity, have opted to hold off on issuance of any
headlines at this time.


.LONG TERM (After 12Z/6AM Wednesday), Issued 314 AM...As the
upper level ridge settles near the Four Corners mid-week, mid-
level moisture will begin to increase from west to east Wednesday
into Thursday. There are now some members of the ensemble systems
that have slowed this moisture return by about 24 hours...with the
mid- level moisture increasing on Thursday rather than Wednesday.

Either way, as moisture deepens either Thursday or Friday, more
widespread thunderstorms can be expected with increasing threats
of heavy rain and localized flash flooding especially across
southern Utah. PWs will remain at or above 90th percentile Friday
into early next week across much of the region. Those with outdoor
plans across southern Utah particularly near slot canyons,
normally dry washes, slick rock areas and those near recent burn
scars should monitor forecasts over the next week.

&&

.AVIATION...KSLC...VFR conditions will persist for the KSLC
terminal through the period. Dry and clear conditions will
continue with diurnally driven winds. A brief northerly wind late
this afternoon will switch back to southerly drainage flow this
evening.

.REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions will persist
for the airspace through the period. Dry and clear conditions
will continue with diurnally driven winds.

&&

.FIRE WEATHER...High pressure becoming established near the Four
Corners region will maintain hot and dry conditions across the
region through Tuesday. Temperatures will trend a few degrees
warmer Tuesday afternoon and challenge a few daily records. RH
will trend lower as well, falling into the single digits across
most low-mid elevations with poor overnight recovery continuing
through Tuesday night.

Monsoon moisture will begin returning to the region by Wednesday,
then increase through the remainder of the week and into the
upcoming weekend. Initially this moisture will be confined to
the mid levels Wednesday, resulting in high based showers and
dry thunderstorms with little if any rainfall. By Thursday, as
this moisture continues to increase, a mixture of wet and dry
thunderstorms can be expected before storms fully transition to
wet with wetting rains more common by the end of the week. With
this increase in moisture, RH will trend higher during the latter
half of the week while temperatures trend cooler.

&&

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

$$

Seaman/Kruse/Mahan

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