St. George, Utah 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

691
FXUS65 KSLC 122003
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
203 PM MDT Sat Sep 12 2026

.KEY MESSAGES, Issued 1159 AM MDT Sat Sep 12 2026...


- An isolated flash flood threat will persist as moisture remains
  in place across primarily southeastern Utah.

- Breezy southwesterly winds will develop Saturday and Sunday
  afternoons, with gusts up to 35 mph on Saturday and up to 40 mph
  on Sunday ahead of a cold front. The highest wind gusts are
  expected across western valleys and in Uinta Co., WY.

&&

.DISCUSSION, Issued 1159 AM MDT Sat Sep 12 2026...
Southwesterly flow will continue to strengthen
across the region ahead of a trough currently pushing into the
PacNW. Gusts this afternoon are expected to reach up to 35 mph
across typically prone areas such as western valleys south of I-80
and across Uinta Co., WY. Tomorrow, as this trough approaches,
southwest flow will further increase though still remain under
advisory criteria around 40 mph in these same areas. High-res
guidance suggests an initial boundary will develop across northern
Utah as a distant shortwave trough rotates through the mid-level
low, which will result in somewhat lighter, westerly flow around
the Salt Lake Valley northward. As a stronger shortwave passes
through the main low Sunday evening and overnight, this will bring
the main cold front through northern and central Utah, resulting
in colder temperatures and a switch to gusty northwesterly winds.
Monday highs will reach 5-10 degrees below normal across northern
areas (near normal across central/southern Utah).

Lingering moisture across southeastern Utah will result in
isolated thunderstorms developing this afternoon between mainly
Lake Powell up into the Uinta Basin. Given that this moisture is
relatively shallow in the mid-levels, the main threat will be
gusty outflow winds, with just an isolated flash flood threat
given any training storms over a sensitive area. Southwest flow
will potentially draw a bit more moisture over the state on
Sunday, however model guidance shows higher uncertainty in the
magnitude of this moisture. Similar to today, the flash flood
threat will still remain fairly isolated despite slightly higher
spatial coverage of storms, particularly considering quicker
storm motions.

The cold front will struggle to scour the moisture out of
southeastern Utah as it dissipates partway through the state, thus
expect isolated to scattered showers and thunderstorms to develop
each afternoon this week. Across the rest of the area, expect dry
conditions and gradually warming temperatures.

Uncertainty increases greatly by mid-week, with potential for
another shortwave trough drawing moisture northward across Utah
late Wednesday into Thursday. Around 30% of ensemble members
suggest this shortwave does not develop, which would likely yield
quieter conditions.


&&

.AVIATION, Issued 1159 AM MDT Sat Sep 12 2026...


KSLC...Light and variable winds currently across the terminal are
expected to transition to a prevailing northwest around 19z. A
normal diurnal wind switch is once again expected between 02-03z,
with increasingly gusty southerly winds developing late night/Sunday
morning in advance of a cold front. Frontal passage is expected to
switch winds back to northwest between 19-21z. VFR conditions will
continue to hold.

REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions are expected to
prevail across the airspace throughout the valid TAF period. Gusty
southerly winds are expected today, largely focused across southern
and eastern portions. Isolated showers and thunderstorms are
expected this afternoon and evening across southern and southeastern
Utah, but will dissipate with loss of solar input this evening.

&&

.FIRE WEATHER...Lingering moisture across southern and eastern Utah
will result in isolated to scattered showers and thunderstorms
Sunday afternoon, with gusty outflow winds and moderate-heavy rain
being the main threats. Large-scale southwesterly winds will
continue to strengthen ahead of a cold front, with gusts up to 40
mph possible across western valleys. A dry cold front will then
move through northern and central Utah before dissipating late
Sunday into early Monday morning. This front will bring a quick
transition to briefly gusty northwesterly winds alongside cooler
temperatures, particularly further north.

Through at least Wednesday, expect a gradual warming trend with
most areas seeing little to no precipitation. Given moisture
hanging on across southeastern Utah, these areas still could see
isolated showers and thunderstorms each afternoon. Additionally,
minimum RH will remain elevated across much of southern and
eastern Utah, exceeding 30 percent in most areas. Western valleys,
especially further north, may continue to see minimum RH in the
upper teens with good overnight recoveries.

&&

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

$$

PUBLIC...Cunningham
AVIATION...Merrill
FIRE WEATHER...Cunningham

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