526
FXUS65 KVEF 140920
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
220 AM PDT Sat Sep 14 2024

.SYNOPSIS...An approaching trough will leading to increasing south
or southwest across the area Sunday and Monday. Moisture will work
its way up the Colorado River Valley and northwest Arizona this
afternoon into Sunday leading to slight chances for showers and
thunderstorms confined to eastern Mohave County on Sunday.
Temperatures will fall well below normal by Tuesday and unsettled
weather will continue through Friday as a reinforcing low pressure
system drops into southern Nevada midweek.

.SHORT TERM...Today through Sunday night.

Today will bring one more day of fairly tranquil weather though some
areas will see 10-15 mph sustained south-southeast winds this
afternoon in response to the broad trough dropping out of the Gulf
of Alaska toward the Pacific Northwest. Another feature to watch is
the moisture associated with Tropical Storm Ileana currently east of
the tip of Baja and moving into northwest Mexico. The HREF and NBM
indicate a modest increase in surface dewpoints in to the mid to
upper 50s working up the lower Colorado River Valley later today and
tonight. It appears this increase will be fairly shallow and the
increasing southwest flow aloft Sunday will begin pushing the
moisture eastward. The HREF and NBM keep any developing convection
Sunday afternoon confined generally east of Kingman. PoP values
have decreased slightly to 20-30 percent for that area.

The increasing south-southwest winds Sunday afternoon will be the
most noteworthy change in the weather as the center of
aforementioned digs over northern California and its base dips over
southern California and Nevada. Widespread sustained winds 20-25 mph
and gusts to 35 mph will result Sunday afternoon. This prompted the
issuance of a Lake Wind Advisory for Lake Mead and Lake Mohave
beginning at noon PDT/MST Sunday and remaining in effect until 8 PM
Monday evening as winds will persist or even increase Sunday night
and Monday. A belt of winds gusting over 40 mph may extend from
northwest San Bernardino County across Death Valley into southern
and central Nye County Sunday night. Will continue to monitor the
potential for additional wind advisories as the event is better
captured by the 48 hour HREF window.

Little change in high temperatures will occur through Sunday with
readings in the 90s across the most desert zones.

.LONG TERM...Monday through Friday

The upper low will be across central California and into central
Nevada on Monday. This trajectory will increase winds additionally
on Monday. The latest ENS EFI is indicating higher values supportive
of an unseasonably strong wind event across much of our forecast
area with the strongest winds over Mohave County. We will be
monitoring how this upper low evolves and considering the need for
wind advisories, particularly for many of the wind prone locations.
The current probability for Las Vegas to see wind gusts above 40 mph
on Monday are 20-30%.

The trough will also usher in much cooler air starting on Monday and
remaining for the remainder of the week. Portions of the Las Vegas
Valley will see temperatures fall into the 50s for the first time
this season on Tuesday morning.

The best precipitation chances with the main low will be across the
Sierra and in the higher elevations of Esmeralda, Nye and Lincoln
Counties Sunday night into Monday with precipitation generally less
than a tenth of an inch and snow levels falling from around 10,000
feet to 8000 feet.

Another system will follow on the heels of the Sunday/Monday system
and impact the area from Tuesday night all the way through Thursday.
This second system will bring another round of breezy winds and
increased precipitation chances with it. Additionally, it will bring
a reinforcing shot of cool air to the Desert Southwest, helping the
cooler than normal temperatures stick around as we head into next
weekend.
&&

.AVIATION...For Harry Reid...Breezy south-southeast winds will pick
up late this morning into early this afternoon. Gust speeds will
peak between 15 and 25 mph with a 10 percent chance of gusts
exceeding 25 mph through the day. Wind direction will start to
gradually shift southwesterly between 00 and 03Z as gust frequency
decreases. Expect hazy skies at times in the Las Vegas Valley due to
wildfire smoke from southern California wildfires, with potential
reduction of visibilities along both the Daggett and Beatty
corridors. No operationally significant cloud cover expected through
the TAF period.

For the rest of southern Nevada, southeastern California, and
northwestern Arizona...Breezy south-southeast winds will pick up
across the region today with gust speeds between 15 and 25 mph. Gust
frequency and speed will decrease around sunset as winds shift from
the southwest. Smoke from southern California wildfires will
continue to impact the Daggett and Beatty corridors through the day
today with hazy conditions possible at all TAF sites. No
operationally significant cloud cover expected through the TAF
period.
&&

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

$$

SHORT TERM...Adair
LONG TERM...Czyzyk/Stessman
AVIATION...Soulat

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