Scientific Forecaster Discussion
fxus65 kvef 182222
Area forecast discussion
National Weather Service Las Vegas Nevada
222 PM PST Sat Nov 18 2017
Synopsis...coldest temperatures of the fall season will occur
across the lower deserts tonight with some areas experiencing their
first freeze of the season. Otherwise, temperatures will warm next
week, with record to near-record temperatures forecast over the
Short term...through Tuesday night.
North wind primarily impacting the lower Colorado River valley has
started to decrease this afternoon. That decreasing trend will
continue into early evening so will go ahead and cancel the Wind
Advisory. A north wind of 10-20 mph is expected to continue through
Saturday before lighter winds on Monday.
Outside, of the lower Colorado River valley where winds will be
light and skies clear temperatures will fall to their lowest values
seen this fall season. First widespread freeze expected in the
Pahrump Valley and in Kingman and surrounding area tonight. A freeze
warning is in effect for those areas. No threat for most of the Las
Vegas Valley but won't be surprised when I come in tomorrow morn to
see an isolated spot on the outer edge of the Las Vegas Valley
briefly touch 32 degrees.
Broad mid-level ridge over the southwest Continental U.S. Through Tuesday will
really start to amplify heading into the Holiday. Model time
height/relative humidity progs insist a decent amount of mid/high clouds will be
topping the ridge Monday and Tuesday.
Long term...Wednesday through Saturday.
Longwave ridging will dominate through the long term period. For the
Wednesday through Thursday period, expect ridging to amplify over
the southwestern conus, with a stream of mid and high level moisture
riding up and over the ridge. This will allow temperatures to Jump
Up to well above normal levels for late November. The current
forecast high in Las Vegas for Thanksgiving day is 78 degrees, which
would break the record for November 23rd of 76 set in 1995.
Relatively light winds and occasional periods of cloud cover can be
expected through the period.
Aviation...for McCarran...northeast winds up to 10 kts through 00z
then becoming westerly under 8 kts overnight. Winds will remain
light through the remainder of the weekend with increasing mid and
high clouds Sunday night into Monday.
For the rest of southern Nevada, northwest Arizona and southeast
California...breezy north winds this afternoon will become lighter
this evening. Stronger north winds will persist along the Colorado
River valley but will also be on a decreasing trend. Clear skies and
VFR conditions expected through the period.
Spotter information statement...spotters are encouraged to report
any significant weather or impacts according to Standard operating