818
FXUS65 KVEF 040916 CCA
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
217 AM PDT Sat May 4 2024

.SYNOPSIS...A potent storm system dropping down from the Pacific
Northwest will move across the region today and Sunday bringing
widespread strong winds and much cooler temperatures. High elevation
snow in the southern Sierra Saturday will spread across parts of
southern Nevada Saturday night and Sunday leading to a dusting of
snow in the mountains. Improving conditions are expected Monday
though temperatures will stay a little below normal much of the week.
&&

.SHORT TERM...Through Monday night.

Anomalously deep and cold low for early May situated off the Pac NW
coast early this morning. Shield of extensive cloudiness is moving
into northern California and northwest Nevada, while precipitation
is confined to western Oregon/Washington.

Leeside surface pressure falls across northern and central Nevada
today ahead of the deep low will induce a tightening pressure
gradient leading to strong southerly winds across the southern Great
Basin and Mojave Desert. Downward momentum transfer of 35 knot to 55
knot winds at H7 will help in the development of 50 to 60 mph gusts
in parts of Inyo, Esmeralda, Nye and western Clark County this
afternoon. Elsewhere, gusts will mostly range between 40 and 50 mph.
The period of strongest winds across parts of southern Inyo,
southern Nye, Clark and northwest San Bernardino Counties will occur
tonight into Sunday morning. Specifically in and within the lee of
the Spring Mountains/Red Rock Canyon that timeframe looks to be
midnight through 9 am Sunday. HiResW-NMM cross section through Red
Rock Canyon and the LV Valley indicates potential 55 knot to 75 knot
winds surfacing within Red Rock Canyon late this evening with the
downslope component weakening after 7 am Sunday. Here in Las Vegas,
surface winds will finally start to diminish Sunday afternoon while
it will remain windy across Mohave and San Bernardino Counties
through late Sunday afternoon.

Am making no changes to our existing products. But with that said,
the Owens Valley and LV Valley bears watching due to potential
downslope winds which creates a higher probability of wind gusts
exceeding 58 mph or reaching warning levels.

Temperatures will stay warm today with dramatic cooldown Sunday
dropping as much as 20 degrees for some spots.

Regarding precipitation. Most of the showers will get hung up in the
southern Sierra through this evening. As the deep low makes it
further into the Great Basin light showers will break out primarily
across south central Nevada tonight and Sunday. There is a chance
for a light dusting of snow as far south as the Spring Mountains.
Forecast of 2" of new snow at Aspendell in the southern Sierra
consistent with forecast 24 hours ago. Less than 1" expected in some
of the higher valley floors of central Nye and northern Lincoln
Counties.

Sunday night and Monday. As the trough moves east precipitation will
come to an end early Sunday evening. Some breezes will exist into
Monday while temperatures start to recover.

.LONG TERM...Tuesday through Friday.

The area will be under a mostly zonal flow with a touch of a NW
component through much, if not all, of the work week as persistent
troughing remains just to our north. At the surface, this results in
breezy afternoons with highs roughly 3-8 degrees below normal across
the area. We`ll remain dry as the troughing to our north has very
little moisture to work with. PoPs stay below 10% through Friday.
&&

.AVIATION...For Harry Reid...Light southerly-to-southwesterly winds
will begin picking up around mid-morning and will continue to
increase throughout the day with 30 to 40 knot wind guts expected
this afternoon and evening. Vicinity blowing dust from the dry lake
beds southwest of the Las Vegas Valley will have the potential to
cause reductions in slant-wise visibility, but there is currently
low confidence/probability whether or not it will cause visibility
reductions at the surface. When looking at the potential for an AWW,
the latest HREF has a 10% to 20% chance wind gusts in excess of 48
knots from 03 UTC to 06 UTC Saturday. Should this come to fruition,
these gusts would likely be from a more west-southwesterly direction
due to downsloping off of the Spring Mountains. Winds will gradually
decrease and eventually turn northwest on Sunday afternoon as the
front moves through the area.

For the rest of southern Nevada, northwest Arizona and southeast
California...The Colorado River Valley and the Las Vegas Valley TAF
sites will see south-southwesterly winds pick up around mid-morning
with 30 to 40 knot wind gusts continuing into the evening hours.
KDAG will favor a more westerly direction with wind gusts jumping
into the 30 to 40 knot range later this morning/early this afternoon
and continuing through the overnight hours. Light and variable winds
will pick up and swing to the south-southeast around mid-morning
with 30 to 40 knot wind gusts continuing into the evening hours.
Showers are expected to develop in the crest of the Sierra this
afternoon and will likely blow over into the Owens Valley into the
vicinity of the KBIH terminal area. There is a 20% to 40% chance
that the precipitation may actually make it to the terminal; should
this happen, precipitation will be of light intensity.
&&

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

&&

$$

SHORT TERM...Pierce
LONG TERM...Salmen
AVIATION...Stessman

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