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Area forecast discussion 
National Weather Service Reno Nevada
223 am PST Fri Dec 2 2016

Synopsis...

Strong easterly ridge winds continue today in the Sierra with
dangerous wind chill temperatures possible in the highest
elevations. Brief ridging returns before another very cold low
pressure system drops into the region late Sunday into Monday. A
warmer and wetter pattern is likely by the end of next week.

&&

Short term...
strong easterly ridge winds are affecting the higher Sierra early
this morning with some of the wind sensors reporting gusts around 70
mph. Peak wind gusts along the Sierra could reach up to 100 mph with
the strong surface gradient in place with the upper level jet. The
strongest winds are expected on the west side of the Sierra, but
wind gusts around 35 mph will create choppy conditions at Lake Tahoe
through the remainder of the day. These strong ridge wind will
continue through this afternoon as the upper level jet sags
southward.

Winds will weaken by the weekend as the surface gradient relaxes and
the upper level jet exits the area. Temperatures will begin to warm
back to above average through the weekend as well as high pressure
returns to the region. Strong valley inversions will likely dominate
on Saturday with only minor warming for the lower valleys, but
mixing should improve by Sunday allowing for a more noticeable
warmup. For Sunday, the breezy conditions ahead of the next system
will allow temperatures to warm into the 50s, which is quite warm
for early December.

Simulations continue to show a slower and more eastward track with
the system for Sunday into Monday. Generally showers appear to
remain well north of Interstate 80 through early Monday morning. The
best moisture and dynamics with the system appear to remain just
east of the region with the initial cold front, so continued to
trend the chances for precipitation downward. One thing to note with
this system is that it continues to look very cold, so although it
is coming in much slower we can expect a significant cold snap by
late Monday into Tuesday. - Edan



Long term...
some minor changes to push the better threat of snow into Monday
night and Tuesday as the slider looks to come in a little later.
Aside from that, few adjustments to the long term.

The initial front Monday morning looks to have much of the
moisture over NE Nevada. As a result, the threat of snow across
western Nevada is looking more limited. The secondary system, an
inside slider, will move through Tuesday morning with a
reinforcing shot of cold air. The GFS is faster and further east
while the ec is slower and west. The ec would favor a quick burst
of snow along the front in western Nevada while the GFS shows a few
snow showers at best. Either way, it will be quite cold with temps
10 degrees below early December averages.

Ridging then builds in for Wed with temps moderating, more so for
the mountains. Then, another system is possible for Thu/Fri.
However, the models continue to show differences with the ec
showing a stronger ridge than the GFS. It would keep much of the
precip in the Pacific northwest along with warmer temps. At this
point, used a blend of them as the ensembles show no preferred
solution at this time.

&&

Aviation...
VFR conditions with some gusty NE winds and mtn wave turbulence
over the Sierra. The valleys will see lighter winds with a gradual
reduction in winds tonight. Lighter winds will continue into
Saturday before the winds become more west and locally gusty
Sunday ahead of a cold front.

&&

Rev watches/warnings/advisories...
Nevada...Lake Wind Advisory until 10 PM PST this evening for Lake Tahoe
in nvz002.

California...Lake Wind Advisory until 10 PM PST this evening for Lake Tahoe
in caz072.

&&

$$

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