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fxus65 kvef 160954 

Area forecast discussion
National Weather Service Las Vegas Nevada
154 am PST Mon Dec 16 2019

Synopsis...high pressure will bring quiet weather through Tuesday
except for gusty north winds down the Colorado River valley. A weak
storm will pass by Wednesday with increased cloud cover, then high
pressure will return Thursday through Saturday. Stronger storm
systems could bring wet periods from Sunday through Christmas.

Discussion...aside from cirrus over southeast CA, skies were clear over
our County Warning Area early this morning. Winds were light, and temperatures were
seasonably chilly. Only impactful weather today and tomorrow will be
gusty north winds down the Colorado River valley. As noted by
previous shift, conditions will be very close to lake Wind Advisory
criteria today, and perhaps Tuesday as well. Tricky forecast in that
different pieces of model guidance not only give different answers
of whether or not advisory criteria will be reached today, but also
whether today or Tuesday will see the stronger winds. Will hit it on
social media today, and let what happens today serve as another
piece of guidance to help make a decision for tomorrow. As also
noted by previous shift, the storm system reaching the West Coast
Tuesday night and crossing our area Wednesday continues to look
weaker with each successive model run. Expect no precip outside of
the Sierra, and little or none there. The storm will reverse the
pressure gradients helping to drive the northerly winds down the
Colorado River valley, thus shutting them down after Tuesday. High
pressure noses back in Thursday, bringing more dry weather through
Saturday. By that time, the next storm system, which looks much more
impressive (at least for now) than the one on Wednesday, will be
nearing the West Coast. As is typical, there is some model spread
with regards to the timing and strength of this storm, as well as
whether there will be one or more additional storms hot on its
heels. The main message is dry weather through Saturday, with
temperatures below normal early in the week rising to near or
slightly above normal at the end of the week, with a chance of a wet
period next week.

Aviation...the main forecast concerns today center
around the breezy northerly winds. An easterly component will
increase today, though how northeasterly vs northerly the winds will
go remains difficult to pin down. Winds calm down once again after
sunset, with another round of northeast winds possible for Tuesday.

For the rest of southern Nevada, northwest Arizona and southeast
California...main weather concern through the period is northerly
winds across the region. The strongest will be in favored areas down
the Colorado River valley, with a more northeasterly direction
across the Mojave Desert, including kdag. Speeds diminish
significantly with sunset, and winds favoring drainage trends
expected tonight.

Spotter information statement...spotters are encouraged to report
any significant weather or impacts according to Standard operating


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