Area Forecast Discussion
Issued by NWS Reno, NV

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FXUS65 KREV 171126
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
326 AM PST Fri Nov 17 2017

.SYNOPSIS...

A cold front moving through the region this morning will bring
lowering snow levels, areas of showers, and gusty winds. Drier
weather and generally light winds return for the weekend followed
by additional chances for wet weather next week.

&&

.SHORT TERM...

Low pressure tracking through southern Oregon this morning is
pushing a cold front through northeast California and western
Nevada. A burst of gusty winds has accompanied the front as it
slides south. Areas, especially south of Highway 50, should see
elevated winds this morning as the front progresses through that
area. Lake Tahoe is currently experiencing southwest winds of
20-30 mph with gusts to 40 mph as the front moves through; however,
winds should taper down this morning by around sunrise or shortly
after so will not issue a lake wind advisory.

As far as precipitation this morning, the best deep forcing along
the cold front appears to be over extreme northern Nevada, southeast
Oregon, and Idaho per cooling cloud tops there. For northeast
California and western Nevada, precipitation/showers near the
front have been more sporadic and lighter with weaker instability
and forcing. Still, based on precipitation amounts and chain/snow
tire restrictions, up to a couple inches of snowfall is possible
in the Surprise Valley and above 5000 feet in Lassen County (closer
to the core of the upper low). Meanwhile, upslope and cold
frontal forcing is providing sufficient lift for more widespread
snow showers in the Sierra with travel restrictions in place for
the passes around Tahoe. Be sure to check road conditions before
traveling in the Sierra or through northeast CA this morning.

Showers should dissipate quickly by mid to late morning behind the
cold front. Tonight through Sunday, quieter weather moves into
the region as high pressure builds overhead. Temperatures will
remain within a few degrees of average for valleys over the
weekend. -Snyder

.LONG TERM...Monday through Thanksgiving weekend...

For next week, the first half is looking to be more active with a
couple of fast moving weather systems which may tap into some
subtropical moisture. Later next week including the Thanksgiving
weekend, the overall trend appears to favor lowered precip chances,
although we can`t rule out the possibility for some light
precipitation at times especially for northeast CA. Overall forecast
confidence is medium to high for above average temperatures and high
snow levels next week, but lower confidence for location and
magnitude of heaviest precip, as medium range guidance scenarios
show a large spread

The first storm of next week is projected to move across the region
Monday and Monday night, with best potential for decent precip
across northeast CA and the northern Sierra, with modest rainfall
amounts for most of western NV. Snow levels near 8000 feet early
Monday are expected to rise above 9000 feet later in the day.

The second storm for Wednesday-Wed night is likely to be even
warmer, with snow levels around 10,000 feet. Model guidance is
showing a narrow moisture band which could bring a period of
enhanced precip across a portion of the Sierra or northeast CA. At
this time we are not anticipating either storm next week to come
close to the intensity of the storm from the past two days, but we
will keep notice on the moisture transport trends leading up to
these events. If either storm shows a substantial upward trend in
precip potential, there could be some hydrologic concerns in areas
that were saturated by this week`s storm, with possible snow melt
contribution to runoff.

Looking into the Thanksgiving weekend, ridging looks to dominate
Thursday and may hold on through much of the weekend, although
trending weaker toward Saturday and Sunday. Precip chances are
currently rather low, but if the ridge weakens more quickly the end
of the holiday travel period could be wet again. Temperatures look to
be quite warm on Thursday with highs pushing well into the 60s for
lower elevations, then easing back to the 50s by next weekend.

Key Takeaways:

* Those with hydrologic interests should pay particular attention to
  storm potential and precip trends for next week, especially after
  the heavy rain and mountain snow from this week`s storm.
* Have Thanksgiving travel plans? Plan on encountering some rain if
  traveling on or before Wednesday, especially if heading into
  northern CA or the Pacific Northwest. While current forecasts are
  indicating mild weather, it is always a good idea to carry chains,
  extra water, and food if planning travel through higher
  elevations.

MJD

&&

.AVIATION...

Restrictions to CIGS/VIS with rain and snow showers in the Sierra
should ease considerably by mid morning as low pressure moves
into northeast NV and Idaho and the showers dissipate. For western
NV and the lower elevations of northeast CA, the main impact will
be higher terrain obscuration with showers/cloud decks and
turbulence with gusty winds (mainly south of Highway 50) this
morning.

High pressure moves overhead for mainly VFR conditions and light
winds for the weekend. -Snyder

&&

.REV Watches/Warnings/Advisories...
NV...None.
CA...None.

&&

$$

For more information from the National Weather Service visit...
http://weather.gov/reno



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