403
FXUS65 KSLC 091757
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
1157 AM MDT Sat May 9 2026

.KEY MESSAGES...

- Near record to record setting heat builds in through early next
  week, with afternoon highs around 15-25 degrees above normal.

- Combination of anomalous heat, single-digit daytime RH and poor
  overnight recoveries, and modestly gusty winds will result in
  areas of locally elevated fire weather conditions.

- The next chance of isolated precipitation arrives midweek, as
  some flavor of trough helps to shift/flatten the ridge.

&&

.DISCUSSION...A pleasant start to the weekend underway, with
satellite only displaying some mid to high altitude clouds
filtering through overhead in the northwesterly flow. A subtle
grazing impulse within this flow will help bring temperatures down
a degree or two most places outside of southern Utah, but in
general still expecting afternoon highs around 5-10 degrees above
seasonal normal. A few isolated showers/thunderstorms may develop
across portions of southeast Utah, but most areas will remain dry.

Over the next several days an expansive ridge of high pressure
will shift into the region, with its influence expected to peak
Monday and Tuesday. Subsidence associated with the ridge will keep
precipitation chances more or less nil, and result in potential
record setting heat with afternoon highs 15-25 degrees above
normal. To contextualize the strength of the ridge, 700 mb
temperatures are progged to increase to around 15C or so. This
would well exceed the climatological 90th percentile of 9C, and
per SPC sounding climatology would even exceed typical 700 mb
temperatures of mid summer. Thankfully being May this won`t result
in quite the oppressive levels of heat one might expect if this
were to arise in summer, but all the same we`ll be looking at
better than 50% odds to see the first 90F day in the SLC area, and
100F day in St. George. Temperatures will still cool at night and
offer some relief, but given these are the hottest temperatures
of the year so far, those working outdoors or recreating should be
sure to have a way to stay hydrated and stay cool.

Scenarios for the post-ridge pattern evolution from midweek to
the end of the work week haven`t changed markedly. Around 45% of
ensemble members maintain a cutoff low off the California coast
and largely dry conditions locally. Around 25% of members have
this feature push inland and phase partially with the northern
stream, offering the best odds of precipitation (which still isn`t
much) and is the coolest scenario. The remaining 30% do little
aside from strengthen the northern stream sufficiently to flatten
the ridge and offer a slight cooldown. In all scenarios the ridge
at least moderates and shifts enough to allow some cooler
temperatures in comparison to the record warmth earlier in the
week.

Uncertainty in the midweek pattern evolution translates onward
towards the weekend, with ensembles still diverging on potential
weather scenarios. Around 35% bring a deeper, cooler, and wetter
trough into the region. 30% have a weak and dry grazing system,
and the remaining 35% have a slightly more amplified but still dry
trough shifting through. Given the high degree of uncertainty and
being a week out, would focus on trends for now.

&&

.AVIATION...KSLC...Operational weather concerns will remain minimal
through the valid TAF period under largely clear skies and stable
conditions. Northwesterly winds currently in place are expected to
become light and variable around 03z prior to returning to the
southeast between 05-06z.

.REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions will persist
for the entire airspace through the period. Dry conditions and
largely clear skies will continue. Modest northwesterly surface
winds this afternoon will trend light and diurnally driven this
evening on through the remainder of the valid TAF period.

&&

.FIRE WEATHER...Modestly breezy northwest winds will persist across
portions of the Wasatch Plateau, Castle Country and the Swell,
and the Uinta Basin through the evening. Any isolated shower or
thunderstorm will quickly diminish through the evening hours.

An anomalously strong ridge of high pressure will build into the
region through the middle portion of the upcoming week.
Temperatures across Utah will push close to if not exceed record
levels, and the ridge will result in very dry conditions. Across
most of Utah daytime minimum humidity values will fall to single
digit values, to at best low teens across portions of the Wasatch
Front and northern high terrain. Overnight humidity recovery will
also be quite poor, especially across the southern half of Utah.
Wind gusts will generally be modest, with some pockets of gusts
generally in the 20-25 mph range Monday and Tuesday. If winds
increase, this could result in areas of locally elevated fire
weather conditions, especially in zones 495/496/497 where fuels
are approaching critical. With wind gusts on Wednesday forecast to
increase more into the 25-35 mph range or so, some locally
critical areas could develop if fuels become sufficiently dry.

There is uncertainty on the exact pattern evolution in regards to
the influence of a trough Wednesday and Thursday, but it is
likely to at least result in a modest increase in mid level
moisture. While isolated in nature, there is around a 10-20%
chance of high based afternoon convection forming over the high
terrain. With limited moisture, this activity would likely be dry
in nature and also carry potential for gusty and erratic outflow
winds.

Moving onward from the end of the work week and into the weekend
temperatures will decrease given the weakened ridge, and while
daytime minimum humidity will remain single digit to low teens,
overnight recoveries will improve somewhat. Models show potential
for another trough over the weekend, with around 35% supporting a
deeper and possibly wetter system. The remaining are more modest
and grazing in nature, offering a slight cooldown and minimal
precipitation chances. In all cases, an uptick in daytime winds
would be likely.

&&

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

$$

PUBLIC...Warthen
AVIATION...Merrill
FIRE WEATHER...Warthen

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