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169
FXUS65 KVEF 201705
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
1005 AM PDT Mon May 20 2024

.SYNOPSIS...An upper level trough moving across our region will
bring slightly below normal temperatures and continued gusty
southwest winds today followed by moderate north winds tonight and
Tuesday. Isolated showers and thunderstorms will occur today in
southeast Nevada and the Arizona Strip near the Utah border. A mean
trough will hold over the western states this week into the holiday
weekend resulting in near normal temperatures with elevated
afternoon winds each day.
&&

.UPDATE...
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An positively tilted upper level trough continued to
dig into the Southwest US through the morning. Satellite imagery
showed this well with a few areas of well defined vorticity lobes
associated with dry slots and cyclonic rotation in the water vapor
imagery. At the surface, the increasing pressure gradient and
incoming system resulted in breezy winds across much of the region.
GUst of 25 to 30 MPH were reported in numerous locations. Other than
some sprinkles over northern Lincoln County, it remained dry through
the morning.

The trough axis is expected to push eastward as it swings into a
more neutral position this afternoon. With limited moisture,
precipitation will struggle to develop. Scattered precipitation
should develop this early afternoon in Lincoln County associated
with an area of better forcing with a weak cold front, which will
shift into northeast Clark County and northern Mohave County later
this afternoon and early evening. Slightly negative LIs and low end
CAPE to around 500 J/Kg should allow for isolated thunderstorms to
develop with the scattered showers. Impacts today from showers and
thunderstorms will be limited however with significant dry air at
the surface, sudden gusty winds to 30-40MPH will be possible. In
general, expect breezy afternoon winds of 25 to 35 MPH, partly
cloudy skies, and cool temperatures compared to yesterday as high
temperatures will drop about 5 degree compared to Sunday`s high
temperatures.
-Nickerson-
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&&

.PREVIOUS DISCUSSION...
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159 AM PDT Mon May 20 2024
.SHORT TERM...today through Tuesday.

Persistent southwest winds gusting between 20 and 30 mph will be the
most noticeable effect of the trough digging over the western states
accompanied by high temperatures pulling back about4-6 degrees from
Sunday. A weak cold front will push through our region tonight and
Tuesday with north winds generally gusting 20 to 25 mph and
temperatures dropping an additional 2-4 degrees.

Limited mid level moisture in a convergence zone across south central
Nevada will slide across Lincoln, northeast Clark and Mohave
counties this morning through the afternoon ahead of the approaching
front which will lead to isolated showers and thunderstorms confined
to these zones. Rainfall amounts should generally be less than a
tenth of an inch and the main hazard aside from lightning will be
the potential for convective wind gusts and the latest HREF
indicates a 30-50 percent probability of gusts greater than 35 mph
in our zones near the border with Southwest Utah. Will be worth
watching, but the probability of any significant weather impacts
is too low to warrant any headlines.

.LONG TERM...Wednesday through Sunday.

A shortwave trough will drop into the Pacific Northwest and
Intermountain West on Wednesday. As this shortwave clears out on
Thursday we will see lingering longwave troughiness across the
southwestern US through the end of the week. As a result,
temperatures will remain in the normal to slightly cooler than
normal range through the end of the week. 20 to 30 mph wind gusts
are expected each afternoon through the end of the week with the
strongest of these winds favoring the western Mojave Desert and
areas of higher terrain. Despite lingering troughiness overhead,
precipitation chances will be limited to none. Another system will
drop into the Pacific Northwest and Intermountain West over the
weekend, which will allow for the continued persistence of slightly
cooler than normal temperatures and breezy afternoon winds through
the weekend.
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&&

.AVIATION...For Harry Reid...After a brief period of light
southeast winds in the late morning and early afternoon, south to
southwest winds with gusts 20 to 25 knots are expected this
afternoon. Winds will continue to gradually subside tonight but
gusty southwest winds will return around midday. Turbulence can be
expected near the mountainous terrain. No operationally significant
clouds or weather expected.

For the rest of southern Nevada, northwest Arizona and southeast
California...Winds will continue to diminish this morning with the
expectation in the Barstow area where southwest-west gusts from 30-
35kts will continue. Gusty west to southwest winds will develop
again over most of the Mojave Desert today, with northwest to north
winds expected across the southern Great Basin. The strongest
afternoon gusts of 30-35 knots are expected from Barstow through
Searchlight to Colorado City. There will be a very small chance for
showers and thunderstorms this afternoon in areas from the Sierra
crest eastward to the panhandle of Lincoln County, but much less
coverage is expected today than what occurred Saturday afternoon.
&&

.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&

$$

SHORT TERM...Adair
LONG TERM...Stessman
AVIATION...Salmen

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