Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Las Vegas Nevada
250 am PDT Friday Aug 29 2014
Synopsis...a pleasant end of Summer Holiday weekend is in store for
the area with dry weather...occasional breezes and above normal
Short term...Labor Day weekend...Friday through Monday.
There will only be minor change in the weather through the Holiday
weekend. A ridge of high pressure over the Desert Southwest today is
dampened as a fast moving open trough moves across the northwest
states and brushes the Great Basin Saturday. This will lead to
increasing southwest to west winds Saturday afternoon with sustained
speeds generally in the 15-20 miles per hour and gusts 25 to 35 miles per hour. High res
models indicate the potential for moderate downslope winds in the
Lee of the southern Sierra with gusts around 40 miles per hour possible for a
few hours late Saturday afternoon and evening. One other thing Worth
noting is that satellite loops showed the eastern Pacific trough
beginning to pull remnant middle and high level moisture off of
decaying Tropical Storm Marie and spreading it across northern
California into Nevada. This cloud cover will be pushed southward
Saturday as the trough axis moves across the region. Sunday
and Labor Day will see dry and decreasing northwest flow aloft
across the region with light winds and slightly lower temperatures.
Long term...Tuesday through Thursday.
Trough dropping into the Pacific northwest Tuesday will shift
overall flow to the southwest and continue to keep things dry. With
trough remaining in place to our north through the forecast period
we can expect breezy conditions each afternoon. Temperatures retain
seasonal values and afternoon highs should hover around the century
mark for Las Vegas next week. The latest runs of the European model (ecmwf)/Gem
continue to show some moisture returning into Arizona late next week
and have light precipitation across parts of Mohave County...but the GFS
keeps the moisture over Mexico. Overall confidence in any moisture
returning is low and will have to wait and see how the models handle
the location of this moisture late next week.
Aviation...for McCarran...light east to southeast winds can be
expected this afternoon and early evening followed by diurnal
southwest winds up to 10kts tonight. Southwest winds gusting around
25 kts can be expected Saturday afternoon with increasing high level
clouds as a trough moves across the Great Basin.
For the rest of southern Nevada...northwest Arizona...and southeast
California...generally light winds can be expected across the region
today with increasing high level clouds across the Great Basin.
Southwest winds gusting 20 to 30 knots will occur across much of the
region Saturday afternoon and evening as a trough moves across the
Spotter information statement...spotter activation is not expected
through the weekend.
For more forecast information...see US on our webpage:
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