780
FXUS65 KSLC 182044
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
244 PM MDT Sat Oct 18 2025

.SYNOPSIS...Conditions will be drier and warmer Sunday with
enhanced west to southwest winds. A cold front Sunday night into
Monday will bring rain and mountain snow to southwest Wyoming and
northern Utah. After largely dry conditions from early Monday
through Tuesday, a storm system will track into southern Utah
Wednesday.

&&

.SHORT TERM (Through 12Z/6AM Tuesday)...Dry, clear conditions are
set up throughout southwest Wyoming and Utah downstream of a
ridge axis to the west. That ridge axis will track across the
region early Sunday. Synoptic flow will transition from the
northwest to zonal and then southwest through Sunday as a longwave
trough digs southeast from the PacNW. This will bring gusty west
to southwest winds, strongest for southwest Wyoming, where peak
gusts will exceed 50 mph. For Utah, the strongest winds will be
near the Idaho and Wyoming borders and for western portions of
Utah. Gusts for these locations will generally range from 25-40
mph. The stronger winds will be associated with warm air
advection, with valley temperatures into the 70s for most of Utah.

The longwave trough will track in from the northwest Sunday night
into Monday. Ensembles are in good agreement that it will graze
southwest Wyoming and northern Utah. The associated cold front
will bring scattered rain showers and mountain snow showers.
Precipitation totals will generally range from a trace-0.1", with
the most precipitation in mountainous terrain near the Idaho
border. Much cooler conditions will build in Monday behind the
front, with precipitation ending as snow to around 6000 feet.
Mountain snow accumulation will be generally less than 1 inch.

Rain and snow will taper off early Monday, but temperatures will
be much cooler. Valley highs will generally be in the 50s, with
the most cooling in southwest Wyoming and northern Utah. Further
south, the grazing storm system will not bring as much cold air
advection, with lower Washington County with highs around 80F. For
northern valleys, specifically those closer to the Idaho border,
clear conditions Monday into Tuesday will bring frost and freeze
conditions.

.LONG TERM (After 12Z/6AM Tuesday)...We begin the long term period
with some of the coldest temperatures of the season so far across
the northern half of the forecast area. Clear skies and continued
northwesterly flow aloft behind the exiting trough will allow
temperatures to dip into the mid-to-upper 30s across the Wasatch
Front on Tuesday morning, with higher elevation valleys across
northern Utah including the Cache Valley and Wasatch Back reaching
the low 20s. Most active agriculture areas are likely to remain
above freezing, except for the northern Wasatch Front where there is
a 40-60% chance for temperatures to dip below 32 degrees.

A closed low originating off the coast of southern California will
lift into the southern Great Basin on Wednesday. Modest moisture
transport into the region associated with this system will result in
increased chances for isolated to scattered showers and
thunderstorms Wednesday into early Thursday morning, mainly across
southern and eastern Utah. Storm total precipitation is still
expected to be overall meager, with most locations seeing generally
less than 0.1-0.25" between Wednesday and Thursday. The NBM 90th
percentile still highlights the southern mountains for potential to
see higher storm totals, suggesting totals between 0.5-0.6"
possible.

A transient ridge passing over Utah and southwest Wyoming yields
dry conditions and seasonably cool temperatures areawide Thursday
into Friday. This ridge will be followed by a longwave trough
moving into the western US through the weekend, which will promote
cooler and more unsettled conditions into early next week.

&&

.AVIATION...KSLC...Diurnal flows and VFR conditions are expected
this evening with winds clocking to southerly around 02z. Tomorrow,
gusty winds out of the south in excess of 20kts will develop after
15z with scattered rain showers developing near the terminal after
21z.

.REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions with diurnal
flows prevail for the remainder of this evening. Tomorrow, a system
clips northern UT bringing gusty winds in excess of 20kts to all
sites except KSGU following 15z. Additionally, gusts in excess of
40kts out of the south-southwest are possible at KEVW. Lastly, rain
showers develop across the majority of our northern UT sites and
KEVW following 21z with a changeover to snow at KEVW just outside of
the TAF period.

&&

.FIRE WEATHER...Dry conditions will continue throughout Utah much of
Sunday. High pressure will track eastward, while a storm system
will track from the Pacific Northwest into Utah. This will bring a
warming trend throughout, with high temperatures of 5-10F warmer
than normal. Strong west to southwest winds will last much of the
day ahead of the storm system. Winds will be enhanced throughout
Utah, but strongest in northern and western Utah, where gusts will
generally range from 25-40 mph. Relative humidity will trend
lower from north to south, with values in the teens for many
locations with gusty winds.

A cold front will track into northern Utah Sunday night. That
will bring scattered showers, rain and mountain snow, from roughly
Utah County to the Idaho border. Precipitation totals will be
light, generally from a trace-0.1", with mountainous terrain near
the Idaho border to get the most. Snow levels will drop to around
5500 feet prior to precipitation ending. Snow accumulations will
be light. Temperatures will be 5-15F cooler from Sunday to Monday,
with greater relative humidity values throughout Utah.

Dry conditions will build in Monday and Tuesday. A storm system
will track in from the southwest Wednesday, with scattered showers
primarily for southern Utah.

&&

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

$$

SHORT TERM...Wilson
LONG TERM...Whitlam
AVIATION...Worster
FIRE WEATHER...Wilson

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