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fxus65 kvef 231003 

Area forecast discussion
National Weather Service Las Vegas Nevada
203 am PST Thu Nov 23 2017

Synopsis...record breaking warmth to continue through the
beginning of the weekend before a strong trough sweeps through the
region and brings a dramatic change to the weather pattern for
the beginning of next week with gusty winds and cooler
&& through Wednesday

Quiet weather will persist through much of the weekend as high
pressure continues to sit over the southwest US. The ridge does
break down tonight through Friday and will likely mean more
clouds than sun for a period before high pressure builds back in
for Saturday. The main story through the end of the week will be
the well above normal temperatures. Expect highs to continue to
run 15 to 20 degrees above normal for many locations. The odd man
out will be Death Valley where a strong inversion has kept it from
mixing out and warming to its full potential. This trend looks
like it should continue through Friday before it breaks the
inversion and climb back into the 90s for the weekend.

By Sunday, the weather pattern is expected to become more active
as a strong upper level trough moves in from the west. There is
still a considerable amount of uncertainty in the models on how
strong this trough will be as it sweeps through later Sunday into
Monday, so didnt make too many changes for this period given the
low confidence. The European model (ecmwf) continues to highlight a significant
system pushing through, while the GFS is more disjointed and not
as deep. Trends may be favoring the weaker and slower solution but
no big shift in the models has occurred as of yet to latch onto.
Depending on how the scenario plays out, watching the potential
for increasing south winds on Sunday then gusty north or northwest
winds Monday and Tuesday behind the system. In addition, some
rain or snow is possible in the Sierra nevadas starting Sunday
night, however did slow down the timing of precip arrival per
model trends until after 06z Monday.

After the upper level trough swings through, temperatures are
expected to drop for the beginning of next week. While not a
major impact as temperatures will only return to more normal
levels, it will be a noticable difference in temperatures between
Sunday and Monday.

Dry weather is expected next week. A few weak low pressure
systems are highlighted in the long term models for next week,
however there is no consistency between models or run to run so
confidence is very low as to when we could see any impacts from
these systems, if we see any at all.

Climate...temperatures will be in record territory over the next
couple of days threatening records that have stood strong for
decades in many instances. Below is a table featuring a few
locations around the region and their current records and year set.

Thursday 11/23 Friday 11/24 Sat 11/25
Las Vegas, Nevada 76 (1995) 81 (1949) 76 (1970)
Bishop, California 78 (1959) 80 (1949) 78 (1954)
Barstow, California 82 (1949) 85 (1949) 81 (1959)
Needles, California 82 (1995) 84 (1949) 83 (1949)
Kingman, Arizona 82 (1915) 84 (1921) 83 (1921)

Aviation...for McCarran...light winds following typical diurnal
patterns are expected through Friday with sct- bkn clouds aoa 20

For the rest of southern Nevada, northwest Arizona and southeast
California...generally light winds through Friday with sct-bkn
clouds aoa 20 kft.

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



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