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Area forecast discussion 
National Weather Service Las Vegas Nevada
312 PM PDT sun may 24 2015

Synopsis...showers and thunderstorms will be mostly limited to
the Sierra and the southern Great Basin for much of the upcoming
week with dry conditions expected elsewhere. Below normal
temperatures Monday will transition to above normal later in the

Short term...through Wednesday night. Satellite loop showed
yesterdays low moving east along the Arizona Mexico border with a
secondary circulation dropping south through the Great Basin. Area
radars showed showers and thunderstorms over Clark...Lincoln and
Mohave counties moving generally southeast. After the secondary
circulation passes through tonight...weak shortwave ridging Monday
will limit thunderstorm chances to the higher terrain near and north
of Las Vegas. By Tuesday another low pressure system will move into
Washington state...but heights will rise a little more over our
area...pushing temperatures to near normal for late may and pushing
thunderstorm chances a little farther north than Monday. Models show
the low over Washington phasing with a weak southern stream trough
moving into the northern Baja California Wednesday...forming a full latitude
trough over the west. However...they also agree on little change in
sensible weather for our area...with thunderstorm chances still
remaining north of Las Vegas and temperatures edging up a couple
more degrees.

Long term...Thursday through Sunday.

Weak trough will still impact the region Thursday with limited
moisture and weak instability over mainly Lincoln County and the
Sierra crest where the best chances of showers and thunderstorms
will remain. Although chances are fairly limited at less than 30
percent in these areas. This trough is expected to exit the region
Thursday night as ridging begins to build over the area. As the
ridge continues to build temperatures will also rise through next
weekend. High temperatures on Thursday are expected to be a few
degrees above normal...but by the weekend are forecast to be around
7-9 degrees above normal. Right now there are some differences
between the operational GFS/European model (ecmwf) models with regards to the
strength of the high over the weekend. The European model (ecmwf) tries to weaken the
high a bit as a trough skirts by to the north while the GFS keeps
the high firmly over the area. If the GFS verifies temperatures
could easily reach the low 100s in Las Vegas with 110 in Needles and
between 110-115 in Death Valley. Right now have kept temperatures
slightly on the conservative side...but if the models keep the high
in place then we will see those hotter temperatures.

Aviation...for McCarran...a few showers and thunderstorms will be
around through this evening with the possibility of one reaching
within 3 sm of the terminal. Gusty outflow winds up to 30kts will
also be possible with any storm. Outside of any storms...winds will
remain southwest around 10kts with ceilings around 10k feet.
Thunderstorm chances will be around again Monday...with a slight
chance of a thunderstorm close to McCarran.

For the rest of southern Nevada...northwest Arizona...and southeast
California...isolated to scattered showers to continue through the
evening...mainly across Lincoln...Inyo...central Nye and Clark
counties. Gusty outflow winds up to 35kts will be possible with any
storm and ceilings around 8-10k feet. Thunderstorms chances will remain
in the forecast Monday with mainly isolated activity.

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



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