Strong Wind in Nevada, December 12, 2018

Area Forecast Discussion
National Weather Service Las Vegas NV
850 AM PST Wed Dec 12 2018

.SYNOPSIS...A swift moving cold front will bring gusty north
winds to parts of the area today along with a slight cooldown for
the later portion of the week. A few additional disturbances are
possible this weekend and early next week...mainly impacting the
Sierra and southern Great Basin with shower chances. Temperatures
will be near to slightly above normal through the period.

&&

.UPDATE...Potent cold front projected to slide through the region
today is just starting to creep into our northern zones this
morning. Winds in Ely have been gusting to near 50 mph in the past
hour with heavy snow reported there along a narrow snow band.
Meanwhile further west, Tonopahs winds have just begun ramping
upward in the past hour as well.  Expect these winds to expand
southward  through the day, and the wind advisory for Esmeralda,
central Nye, and Lincoln counties look good. I also added a few snow
showers to the higher elevations of northern Lincoln county through
early afternoon given the observations just to the north.

Further south, expect north breezes to increase by mid afternoon and
become locally gusty, but well below wind advisory levels.
Temperatures this morning are running on par with yesterdays
observations at the same time. Still the chance we may overachieve
on the temperatures with the added mixing, but opted against making
any changes to the forecast highs this afternoon as temperatures
near 850mb will be cooling at the same time.

-Outler-

&&

.SHORT TERM...Today through Friday.

Based on current satellite imagery, the aforementioned quick moving
weather system has begun to aid in high clouds into southern
NV/southeast CA this morning. The trough responsible is currently
digging into the northern Great Basin region and will continue its
southeastward journey toward the four corners region later today.
The main impacts with this fast moving system will primarily be
gusty north winds along and behind a cold front. The strongest winds
will be across our northern zones as the trough quickly digs further
east and out of our area later this afternoon. High resolution
models are still indicating that Esmeralda, Nye and Lincoln counties
will likely see gusts of 40-50 MPH today, so the previously issued
Wind Advisory looks good. Did take a look at a possible Lake Wind
Advisory for Lake Mohave this afternoon, but decided against it
because MOS guidance is not quiet hitting the 25 mph sustained
criteria and the 700mb temperature gradients do not look to be all
that impressive/favorable down the Colorado River Valley. That being
said, the Bullhead City area, just south of Lake Mohave, will be
quiet gusty as it usually is with north wind events but winds should
remain below wind advisory criteria. Skies will return to mostly
clear behind the fropa later this evening.

By Thursday, a ridge will move into the southwest bringing dry
conditions and mostly clear skies with some passing high clouds.
Cooler temperatures from the quick cold front will bring high
temperatures to near seasonal normals.

By Friday, a trough off the Pacific NW coast will push the ridge
eastward and move across the western CONUS mainly increasing cloud
cover and bringing southwest flow to the region. Most of the mid
level moisture will likely be intercepted by the Sierra crest but
kept slight chances for light snow in for possible spill over near
ridgetop Friday afternoon and evening. Elsewhere, expect dry
conditions and mostly cloudy skies.

.LONG TERM...Saturday through Tuesday. Active pattern to continue
through much of the period over the Pacific, but most of the impacts
will be focused north of our area. Expect dry weather areawide
Saturday under zonal flow, with a slight chance of snow in the
Sierra Sunday as the flow buckles more southwesterly ahead of
deepening low pressure in the eastern Pacific. By Sunday night and
Monday, an interesting wrinkle develops. The models agree on the
existence of a weak trough well ahead of the main storm, but do not
agree on its location. The ensemble members which are farthest west
depict this trough west of the Baja, where it taps into the slug of
tropical moisture currently seen near 16N 126W (satellite blended
total precipitable water estimates are around 2.2 inches). These
ensemble members then bring the trough north across the Baja and
into our area, which would spread precip chances across the eastern
half of our CWA if it were to verify. That said, a small minority of
the ensembles show this occurring, with more members showing the
trough going farther east, missing our area and/or not picking up
the moisture in the first place. Thus, did not introduce PoPs at
this time, but will see how the models trend with this feature. The
main low comes into the West Coast Monday, although the models still
disagree on whether it remains an intact full latitude trough or
splits into northern and southern pieces. With the lack of
confidence in the details, kept PoPs slight chance to low end
chance, and focused on the higher terrain north of Las Vegas. By
Tuesday, this storm is moving away to our east, with a large area of
high pressure building in the eastern Pacific. If this pans out, it
could bring a period of quiet weather.
&&

.AVIATION...For McCarran...Light and diurnal winds will continue
until a push of north winds move through the valley later today
arriving by 19-20Z this afternoon. Expect sustained NNE winds of
10-14 kts with gusts in the low 20s to continue through the
afternoon. Light diurnal winds will resume overnight tonight
around 07-09Z with very light winds expected through tomorrow. SCT
to BKN high clouds will quickly become FEW later this afternoon.

For the rest of southern Nevada, northwest Arizona and southeast
California...Light and diurnal winds will continue until a fast
moving cold front brings a push of north winds across the region.
Gusty north winds will begin later this morning and continue
through the afternoon across most TAF sites with gusts to 20-25
kts. Light and diurnal winds will resume at most TAF sites
overnight tonight with the exception down the Colorado River
Valley, where elevated north winds will continue through the
overnight period. SCT to BKN high clouds will quickly become FEW
later this afternoon. &&

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

SHORT TERM/AVIATION...KRYSTON
LONG TERM...MORGAN

For more forecast information...see us on our webpage:

http://weather.gov/lasvegas or follow us on Facebook and Twitter