Area Forecast Discussion
Issued by NWS Salt Lake City, UT
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075
FXUS65 KSLC 091843
AFDSLC
Area Forecast Discussion
National Weather Service Salt Lake City UT
1243 PM MDT Fri Oct 9 2026
.KEY MESSAGES, Issued 1001 PM MDT Thu Oct 8 2026...
- Widespread moderate to heavy rainfall threat increases late
Saturday through Sunday as a remnant tropical system and
associated deep moisture lift through and interact with an
approaching trough. Widespread water amounts of 1 to 3 inches
are forecast, with locally higher amounts in excess of 3 inches
possible, particularly in high terrain and areas along and
northwest of the circulation track.
- There is also a wind threat associated with this storm,
particularly in the higher terrain, with ~50% chance of wind
gusts in the mountains near the circulation gusting 50+ mph and
~30% chance of wind gusts 58+ mph.
- A closed low will slowly meander across the Great Basin Monday
through Wednesday with scattered showers and thunderstorms
remaining and snow levels falling to 8500-9000 feet.
&&
.DISCUSSION, Issued 1001 PM MDT Thu Oct 8 2026...
Ongoing weather pattern has resulted in another very
mild day this Thursday, with temperatures generally 10 to 15
degrees above normal. Very limited mid level support and moisture
did result in some isolated showers and thunderstorms, largely
over high terrain. With lack of heating, models support the
ongoing activity fizzling out, leading a dry night across the
region with mild overnight lows. Friday then looks to see a
similar pattern with well above normal temperatures and the
development of some isolated showers and thunderstorms across the
region.
Saturday will see the forecast pattern start to change. A trough
will continue deepening southward from the PacNW enhancing deep
southwesterly flow across the Great Basin and Intermountain West,
while at the same time Tropical Storm Rachel is forecast to be
approaching the Baja Peninsula. The trough will continue to deepen
into Sunday, helping pull a weakening Rachel northward and
accelerate. Moisture will continue to overspread the area, and the
remnants of Rachel are most likely to then pass through the area
sometime Sunday into Monday. In regards to impacts and specific
threats, one area of uncertainty that will be key is the exact
track of Rachel. Currently along and north/northwest of the track
is where the highest signal for the most rainfall is, with more of
the strong wind component and possible severe weather threat
expected on its eastern flank. Rachel is forecast to make a sharp
easterly turn overnight into Friday morning, and how quickly this
occurs will likely play a key part in if the future track shifts
more westerly or easterly.
Looking closer at Saturday, with the deep southwesterly flow
overhead, breezy conditions are expected to develop by Saturday
afternoon with widespread gusts around 30-45 mph. The strongest
signal is noted across portions of the West Desert, where there is
around a 30-50% chance of winds pushing into Wind Advisory levels
(3 hours or more of gusts in excess of 45 mph). Aside from the
wind, the increasing moisture associated with Rachel will result
in a corresponding increase in shower and thunderstorm chances
across the region. With shear increasing, a few more organized
thunderstorms may be on the stronger side.
On Sunday the threat of widespread heavy rainfall, strong gusty
winds (especially over high terrain), and severe weather all
increase. As previously mentioned, to an extent the exact
placement of highest threat areas will be track dependent, which
is still an area of uncertainty.
For rainfall, the forecast hasn`t changed significantly.
Widespread amounts of around 1-3" with locally higher amounts
(especially favored southerly aspects of high terrain) remains
forecast by Monday morning. There is also around a 10% chance of a
somewhat narrow swath of heavier rain ~2" or so across a portion
of northern Utah where favorable interactions with the trough may
occur. Excessive rainfall will be possible, especially in
typically rain sensitive basins (recent burn scars, slot canyons,
dry washes, slickrock areas). Additionally, the widespread
moderate to heavy rainfall will result in a response to area
creeks and rivers (see hydrology section).
For wind, continued gusts around 30-45 mph are expected near the
remnant circulation, and especially east to southeast. Some models
have also indicated a localized potential for some easterly
downslope enhancement off of terrain, though this threat would be
highly dependent on the exact track. Higher elevations, especially
areas in the mountains, will see the best potential for more
persistent gusts in excess of 50 mph. Some models also suggest
gusts to or in excess of 70 mph possible at some of the higher
peaks around the region, such as in the Uintas. Depending on exact
timing, strong winds may carry over into early Monday with the
circulation`s path.
The severe threat Sunday will most likely be maximized from mid
morning on through early evening as daytime heating and
instability increases. Given the synoptics overhead with a
decaying circulation lifting through, deep layer shear is progged
to be on the order of 40-60 kts, and effective storm relative
helicity around 100-200 m2/s2. This supports elongated hodographs
curving with height, translating into a low end tornado threat
particularly for any more discrete organized cells. Again, this
would most likely be favored on the eastern flank of Rachel`s
track.
Uncertainty grows pushing towards midweek, with models generally
supporting the broader trough cutting off and subsequently
meandering eastward. While there appears to be less support for
potential interaction with more tropical remnants, there appears
to be enough moisture within the trough to maintain elevated
precipitation chances and further widespread rainfall/snow above
8500-9000 ft or so. Given saturated soils in the wake of Rachel`s
remnants, will have to monitor for any heavier pockets of
precipitation.
&&
.HYDROLOGY, Issued 255 PM MDT Thu Oct 8 2026...
Widespread precipitation of 1 to 3 inches, locally
in excess of 3 inches, particularly across southerly facing
mountain aspects, between late Saturday and Monday morning.
Expect many area waterways including streams, rivers, normally
dry washes, creeks, and slot canyons to have rising, fast flows by
Sunday evening. Current forecasts do not bring any rivers to
flood stage, but this will be monitored as the fine details of
heavy rain bands become more confident. Those with activities
near rivers, streams, creeks and recent burn scars should closely
monitor the forecast over the next several days. Those with
outdoor plans Sunday onward that include any travel near waterways
across Utah should consider alternate plans. Scattered showers and
thunderstorms will remain possible through at least Wednesday, but
these rates will generally be lower, but areas that receive a lot
of precipitation during the weekend will be much more sensitive to
any additional rainfall.
&&
.AVIATION, Issued 553 AM MDT Fri Oct 9 2026...
KSLC...VFR conditions will continue at the KSLC terminal through the
TAF period. Winds are expected to remain southerly through the day
today, although there is a 15 percent chance of a brief shift to
northwest within the 21-00z timeframe. A few high-based showers and
thunderstorms may develop in the vicinity of the terminal after 21Z
with some increase in coverage in the overnight hours.
REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions will prevail
across all regional terminals through the TAF period. Diurnal winds
this morning will trend more southerly this afternoon. Isolated
showers and thunderstorms will develop over the higher terrain this
afternoon, with more focus on northern Utah overnight. These storms
could bring some gusty and erratic winds, lightning, and brief
mountain obscurations.
&&
.FIRE WEATHER...Ahead of Tropical Storm Rachel, a system will begin
to push southeast with widespread gusty winds developing this
evening through early next week. Through this weekend, widespread
wetting rain is expected across the entirety of the state as the
remnants of Rachel move into the area. Following Rachels
departure, a cool and dry pattern is forecast to develop around
midweek next week.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Wind Advisory from 3 AM Saturday to 6 AM MDT Sunday for
UTZ101>109-115-116-118-119-122-126-127.
Flood Watch from late Saturday night through Monday afternoon
for UTZ101>112-114-115.
Flood Watch from Saturday afternoon through Monday afternoon for
UTZ113-116>131.
High Wind Watch from Sunday morning through late Sunday night
for UTZ115>117-119-122-125>127.
WY...None.
&&
$$
PUBLIC...Warthen
AVIATION...Cheng
FIRE WEATHER...Worster
HYDROLOGY...Mahan
For more information from NOAA`s National Weather Service visit...
http://weather.gov/saltlakecity
