Area Forecast Discussion
Issued by NWS Reno, NV
FXUS65 KREV 250412
Area Forecast Discussion
National Weather Service Reno NV
912 PM PDT Fri Mar 24 2017
Precipitation has been quick to end behind today`s cold front
with locations north of Highway 50 mainly dry outside of a few
isolated showers stretching from Truckee to Pyramid Lake. Farther
south, from approximately Tioga Pass to Winnemucca (and areas
south and east), precipitation continues along the frontal
boundary. Light snow remains possible through the evening on
Highway 395 through southern Mono County and Hwy 203 leading into
Mammoth, but any accumulation will be minimal outside of areas
closer to Mammoth Mountain.
The upper level trough is shifting inland tonight with radar and
satellite trends showing showers developing on western Sierra
slopes. This is likely to bring additional light snow showers in
the Sierra and Tahoe region, however with only minimal snow
amounts expected, will go ahead and cancel the winter weather
advisory for the Tahoe Basin. -Dawn
.PREVIOUS DISCUSSION... /Issued 256 PM PDT Fri Mar 24 2017/
Active weather pattern will continue through early next week as a
couple of springtime storms bring mountain snow and valley rain.
Travel impacts are likely in the Sierra tonight and again Sunday
night into Monday. Breezy winds may produce choppy lake conditions
at times through the weekend along with turbulent air travel.
Cold front associated with the current storm system was pushing
across the Tahoe basin and Reno-Sparks vicinity early this
afternoon, producing a short period of enhanced snow around the
lake and steady rain in lower elevations. This front will
continue to move south through tonight and slowly weaken, shifting
the best snow chances southward to Alpine and Mono counties.
Additional snow amounts of 2-5 inches are likely in the advisory
area around Tahoe, with slightly higher amounts south of US-50
along the Sierra crest. Farther north, additional snowfall will be
less, with most of the snow behind the front more confined to
areas near the Sierra crest and far western Lassen County.
Therefore we will cancel the Winter Weather Advisory for Zone 71.
For western NV, the best chance for rain will shift east to areas
east of US-95 this evening where up to 0.25 inch is possible,
while elsewhere rainfall amounts will be lighter.
For Saturday, a weak trough passage will keep the possibility of
showers going mainly through the morning with snow levels
generally around 5000 feet, but little to no additional
accumulations are expected.
The next storm system for the late weekend into Monday looks to
be less organized, with only some light warm-advection type rain
and snow during the day with little to no accumulations. The best
chance for accumulating snow will be Sunday night--although
current QPF projections only support a few inches from northeast
CA into the Tahoe basin and western Mono County, and 4-8 inches
near the Sierra crest. Even these lighter snow amounts could
produce some travel impacts for the Monday morning commute near
the Sierra. For western NV, light rain and snow showers are
possible with the cold front passage early Monday morning but are
unlikely to produce significant travel impacts. Then during the
day Monday, cyclonic flow aloft behind the upper low will keep the
potential for snow or pellet showers going. Brisk northwest winds
will make for a chilly afternoon as highs only reach the lower
50s in western NV and lower 40s near the Sierra. MJD
LONG TERM...Tuesday through Friday...
A quieter pattern will unfold as ridging tries to establish itself
for a good part of the upcoming week. On Tuesday, a shortwave
ridge sets up across northern California and Nevada yielding a
trend towards warmer conditions beginning mid-week. There is some
potential for a brush-by system Thursday but this has been
trending towards staying a little farther north with the best
potential for shower activity remaining north of I-80. Confidence
in the southern extent of the trough is relatively low, so will
leave slight chance of precipitation across southern areas at this
Thereafter, model guidance shows good agreement even a week out of
establishing a broad upper level ridge across the eastern Pacific
basin. This pattern would favor a more northerly storm track which
would diminish our precipitation potential heading into next
weekend. Did warm high temperatures as well with this solution in
mind. Could see temperatures warm above season averages with
highs in the mid to upper 60s across western Nevada and lower 50s
for Sierra valleys. Fuentes
Main cold front has pushed through KTRK, KTVL, KRNO, and KCXP
with post-frontal showers expected to diminish through early
evening. Periods of MVFR Cigs/Vsbys are possible in the post-
frontal band of showers through about 03-04z for Tahoe and western
Nevada terminals (05-06z for KMMH).
Most showers should weaken considerably by 03-04z but a second wave
of weak upslope showers may be possible for KTRK/KTVL/KMMH after 12z
Saturday morning but at most brief MVFR conditions and mountain
obscuration is expected.
Turbulence across the ridgetops should weaken after 06z tonight as
stronger winds aloft near ridge level weaken with trough pushing
After a brief break early Sunday...another storm system will move
through the region late Sunday into Monday. This one looks similar
to today`s system, except most of the precip is likely to occur
during the nighttime hours. Fuentes
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