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fxus65 krev 082104 

Area forecast discussion
National Weather Service Reno Nevada
104 PM PST sun Dec 8 2019


A quiet weather pattern will be in place over the next couple of
days with potential for valley fog in the morning. A weak weather
system could bring light snow showers to the mountains from late
Tuesday into Wednesday. A stronger weather system, with high snow
levels, could arrive by Friday.


Short term...

There will be a break between storms tonight and Monday. However,
the recent heavy rain along with melting snow could create some
travel hassles tonight. Wet roads and sidewalks will freeze
creating slick and icy spots. Also, freezing fog is a good bet
for many valleys in the Sierra and along the Sierra front tonight.
Those traveling overnight or commuting tomorrow morning may need
to leave extra time because of icy roads and poor visibility due
to fog.

Otherwise, a break in the weather, with light winds both in
valleys and at ridgetops, will persist through tomorrow. Westerly
winds may increase for Sierra ridges staring Monday night ahead
of the next (weak) low-pressure system. Jcm

Long term...Tuesday through the winter solstice...

A few weather systems are forecast to pass through the region over
the next two weeks.

First system is set to arrive late Tuesday afternoon and be gone by
Wednesday morning. Not much to write about here, with a just a few
light snow showers in the Sierra. Accumulations should stay at or
below a couple inches.

Next system should set up a bit farther to our the north starting
Thursday, which means a warm up is on tap for middle and end of the
week. Ensembles also predicting high probability of weak Arkansas reaching
the northern California coast and pushing inland with this system,
which could lead to some decent precipitation totals Friday into
Saturday. Snow levels here could get rather high 8000-9000 feet for
the Tahoe basin and Mono County. Definitely something to keep an eye
on over the next few days with saturated soils and and potentially
high snow levels.

Looking ahead to the week of Dec 15-21, ensembles continue the
active pattern with troughing along the West Coast and two systems
arriving around Dec 18 and Dec 20-21. This is a bit beyond the
reliability of the atmospheric river tools (10 days), so difficult
to give much confidence if these will be significant events. However
the Dec 20-21 is the kickoff weekend for Holiday travel, so even a
small event could be impactful for Sierra travel. Brong



Fog and low clouds are expected to develop tonight for many Sierra
valleys and along the Sierra Front Range. Confidence is high for
dense fog at ktrk after midnight. There is also a good chance for
fog or low clouds to develop tonight at ktvl, krno, kmmh, kcxp
and krno and at other Sierra terminals. This fog could create
IFR/LIFR conditions and icy runways tonight into Monday morning.

Otherwise, light winds are forecast both in valleys and ridges
through tomorrow. Westerly ridge winds may increase Monday night
into Tuesday ahead of the next low-pressure system. This next
system will bring chances for mountain snow showers Tuesday
afternoon into Wednesday. A stronger weather system with high
snow levels could arrive by Friday. Jcm


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