924 
FXUS65 KSLC 070909
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
309 AM MDT Tue Oct 7 2025

.SYNOPSIS...Dry conditions will continue over Utah and southwest
Wyoming through Wednesday with a steady warming trend. Tropical
moisture will spread into the area Thursday into Friday before a
cold trough tracks across the area during the weekend. 

&&

.SHORT TERM (Through 12Z/6AM Thursday)...The Rex Block pattern
currently along the Pacific coast this morning will break down 
later today as a Pacific Northwest trough moves the ridge 
eastward as it approaches the coast. Conditions will stay dry over
Utah and southwest Wyoming with maxes running near to a few
degrees below normal for this time of year. 

As the Pacific Northwest trough parks itself along the coast on
Wednesday, southerly flow will start to increase over the area,
helping temperatures warm to in excess of 5F above seasonal
normals with dry conditions continuing to persist. 

.LONG TERM (After 12Z/6AM Thursday)...The synoptic set up Thursday 
will be similar to earlier in the week. A ridge of high pressure 
will stretch from the southern plains to the southwest U.S. A 
longwave trough will be off the PacNW coast. Remnants from a 
tropical system in the eastern Pacific will be off the coast of Baja 
California. Moisture associated with the tropical system will 
increase from south to north through Thursday, with models bringing 
precipitable water values of 0.75-1" for southern Utah. Forcing will 
be limited, with weak shortwaves in the southwest flow, but that 
will be enough with the increasing moisture for scattered showers 
and thunderstorms for southern Utah. Rain will likely not taper off 
into the evening, but rather pick up with the strong moisture 
advection and more shortwave energy ahead of the longwave trough.

Precipitable water values will increase to 1-1.25" for southern Utah 
Friday. Forcing will be better compared to Thursday as the longwave 
trough tracks inland. Light to moderate rain from Friday will 
continue through Saturday morning, then taper off through the 
afternoon. There is uncertainty on where the greatest rainfall 
totals will be, but models highlight an area from roughly St. George 
through Moab and south as where the core of the most precipitation 
will be. Locations in that portion of Utah are forecast for 1-2" of 
rainfall from Thursday through Saturday. Flood and flash flood risk 
will undoubtedly increase for prone locations like slot canyons, but 
also urban areas.

Moisture will enhance throughout southwest Wyoming and Utah Friday, 
with 0.75-1" precipitable water values. Conditions will be similar 
to southern Utah Thursday, where scattered showers and isolated 
thunderstorms are likely. Rainfall totals will be relatively light 
Friday. Moisture content will increase Saturday and longwave trough 
will continue to approach. Models are in good agreement that a cold 
front will track into northern Utah sometime Saturday, most likely 
the afternoon or evening. As moisture increases and the longwave 
trough tracks closer, rain showers will transition to more 
consistent light to moderate rain Friday night. Rain will continue 
through much of Saturday. Rain totals will be lighter than southern 
Utah, with a range from around 0.5-1.0" from Friday night through 
Saturday. 

Strong cold air advection will come with the cold front. High 
temperatures for valleys Thursday will be around 80F. Conditions 
will cool each day as the storm system tracks in. Behind the front 
Sunday, valley high temperatures will be in the 50s for most of 
Utah. Snow levels will lower to roughly 7500 feet, with accumulating 
mountain snow Saturday into Sunday. Accumulations will generally 
range from 1-4 inches for the Wasatch and Uinta Mountains.

The trough axis will push through early Sunday with precipitation 
ending. Largely dry conditions will last through early in the week 
with valley high temperatures generally in the 50s.

&&

.AVIATION...KSLC...Clear conditions will last through the day with 
light southeast winds transitioning to light northwest winds around 
18Z.

.Rest of Utah and Southwest Wyoming...Clear conditions will last 
through the day with light winds.

&&

.FIRE WEATHER...Dry conditions will continue today and tomorrow over
the area, with high temperatures moving above seasonal normals by
Wednesday afternoon. Southerly flow over the area will increase
beginning Wednesday, drawing a significant amount of tropical
moisture into southern Utah by Thursday, spreading into the
remainder of the area by Friday. This will result in the potential
for widespread precipitation, particularly for southern and
eastern portions of Utah, through Saturday. A Pacific storm system
crossing the area late Saturday into Sunday will bring a
heightened potential for precipitation for northern Utah along
with much cooler temperatures.  

&&

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

$$

SHORT TERM/FIRE WEATHER...Traphagan
LONG TERM/AVIATION...Wilson

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