474
FXUS65 KSLC 041017
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
417 AM MDT Fri Jul 4 2025

.SYNOPSIS...Afternoon convection is expected across northern Utah
today, with potential for isolated severe wind and hail. Across
portions of southern and western Utah, dry and modestly breezy
conditions yield areas of critical fire weather conditions. High
pressure returns from the weekend onward.

&&

.DISCUSSION...This morning`s mid-level water vapor satellite imagery
depicts Utah and southwest Wyoming currently wedged between an
upper- level low exiting into the northern Rockies and a shortwave
trough lifting into the Great Basin. Remnant instability from the
exiting low has allowed shower activity to continue overnight
across portions of eastern Utah, but is expected to gradually
taper off over the next couple of hours. A more robust area of
shower activity is also ongoing across northeast Nevada and
northwest Utah early this morning, associated with increased
instability ahead of a the aforementioned trough. Recent high-
resolution guidance supports these showers continuing to move
northeastward across far northern Utah through late morning. A
few lightning strikes have already been observed with isolated
stronger cells within the area of activity across northeast Nevada,
so can`t rule out a couple strikes as these showers move across
northwest Utah through this morning.

As this trough continues to lift through the Great Basin this
afternoon, modest forcing associated with this system will couple
with remnant monsoonal moisture and efficient daytime heating to
produce widely scattered showers and thunderstorms across northern
Utah. Storms that develop this afternoon will have some shear to
tap into, especially across northwest Utah and across the Wasatch
Front, which may lead to some more organized, stronger cells in
these areas. As such, the Storm Prediction Center has placed these
areas under a Marginal Risk (Level 1 of 5) for isolated severe
wind gusts and hail. Given numerous events/festivities associated
with the Independence Day holiday, those planning or attending
will want to keep an eye on the forecast and how the weather
ultimately evolves through the day. Be prepared to head indoors if
storms approach.

In addition to afternoon convection, the aforementioned trough is
expected to bring increased southwesterly flow across the region
today. Expect an increase in afternoon winds today, especially
across the West Desert and portions of southwest Utah. These
winds, in conjunction with low daytime RH values, will result in
areas of critical fire weather conditions. See Fire Weather
section below for more details. Please check with local officials
regarding firework/fire bans and restrictions to reduce the
threat of wildfire ignitions today.

High pressure builds in quickly by Saturday, though a closed low
off the coast of California keeps temperatures moderated through
Sunday. This low is expected to retrograde off the coast early
next week, allowing a ridge to gradually strengthen across the
western US through the end of the week. As such, temperatures are
expected to climb well above average through the week, with
widespread areas of Moderate and locally Major HeatRisk developing
by mid-week.

&&

.AVIATION...KSLC...East-southeast to southeast winds will continue
at the terminal through 14Z, thereafter becoming southerly and
more gusty. Isolated thunderstorms will develop in the vicinity of
the terminal as early as 19Z and may periodically impact the
terminal through about 02Z. Any thunderstorms will be capable of
wind gusts in excess of 50 mph and hail up to 1 inch. Temporary
periods of IFR conditions near thunderstorms will be possible.

.REST OF UTAH AND SOUTHWEST WYOMING...Afternoon convection will
develop and impact terminals across northern Utah, mainly near and
north of a line from KENV to KU14. Strong winds in excess of 58
mph and hail up to 1 inch will be the main threats, along with
lightning and brief heavy rain. Thunderstorms will develop after
18Z and clear Utah by 02Z. Temporary periods of IFR conditions
near thunderstorms will be possible.

&&

.FIRE WEATHER...Remnant instability from an exiting low pressure
system has allowed for some scattered shower activity across
portions of eastern Utah early this morning, but is expected to
taper off through the remainder of the morning. Another weather
system moving into the Great Basin today has introduced increased
instability across portions of northwest Utah this morning,
resulting in scattered showers and even some isolated
thunderstorms across this area. Activity may taper slightly mid-
morning, but is expected to invigorate into more widely scattered
showers and thunderstorms across northern Utah this afternoon.
Any storms that develop across this area today will be capable of
producing gusty outflow winds in excess of 50 mph, in addition to
small hail and frequent lightning. This weather system also brings
increased southwesterly flow across the region today, mainly
across the West Desert and far southern Utah. Wind gusts of 30 to
35 mph are expected to develop this afternoon as a result, and in
conjunction with very low daytime RH values, will lead to areas of
critical fire weather conditions. High pressure builds through
the remainder of the weekend, resulting in a gradual warming trend
into early next week with increasingly poor overnight recoveries.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Red Flag Warning from noon today to 9 PM MDT this evening for
     UTZ492-495-497-498.

WY...None.
&&

$$

Whitlam/Kruse

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http://weather.gov/saltlakecity