Area Forecast Discussion
Issued by NWS Reno, NV
FXUS65 KREV 162241
Area Forecast Discussion
National Weather Service Reno NV
241 PM PST Mon Jan 16 2017
Inversions and poor mixing will continue into Tuesday. More fog
formation is likely tonight with clear skies and cold
temperatures. The next significant weather period is expected to
begin late Wednesday. There is potential for mountain snow and
valley rain as another storm system moves into the region
Wednesday night into Thursday. More storms are possible Friday
into the weekend with snow at all elevations.
The short wave that passed by last night has resulted in clearing
skies for the valleys today. The stratus has been dissipating the
last few hours and will continue into sunset. While this is a
boon for today, it may actually create worse conditions tonight
than the past few nights. Clear skies and valley snow cover will
result in colder temperatures. In addition, the little melting
that has occurred beneath the inversion will result in more
widespread freezing fog formation. I have expanded the freezing
fog for most lower valley locations tonight, including the Sierra
Front. Right now it is only areas, but it may become quite
widespread as this is a classic fog pattern for Western NV.
Conditions will improve during the day Tuesday into Tuesday night
before the next system moves in. This is looking more like a weak
AR event as the storm splits as it approaches the coast. Ahead of
it, winds will increase Wednesday, but they do not appear to be
very gusty with peak gusts around 40-45 mph for the valleys into
the evening. Wind prone areas will be higher while ridges may
peak at near 100 mph.
While the moisture will be quite deep even as it splits, the
weaker forcing will result in much lighter precip amounts than
seen last week. In addition, spillover is looking less robust as a
result of the split with the winds aloft not very favorable as
they weaken in mid levels. The best shot at moisture will be Wed
afternoon into Thurs morning. Snow levels still look to start at
7000 feet then fall to the valley floors Thursday morning.
Around a foot of snow is still possible for the Sierra Crest with
a few inches down to 6000 feet or so. Western NV rainfall amounts
look to be a 1/4 inch or less at this time which will greatly
reduce the threat of any flooding.
With the splitting of the system, I have decided to hold off on
any statements for snow. It is still possible it could split more
and the Sierra would only see very light snowfall. Otherwise, snow
showers will continue in the Sierra Thursday into Thursday night
in light upslope flow. Temperatures will be cooler with highs a
few degrees below average. The next storm then looks to begin late
Thursday night, and snow levels look to start near the valley
floors with that one. Wallmann
.LONG TERM...Friday through Monday...
Forecast is still on track for a very active week. After the
weak AR system exits the region on Thursday, we are looking at
two more systems quickly following on its heels. These systems
appear to be quite cold, with the potential for accumulating snow
down to all valley floors. Snow levels will remain down to all
valley floors through the entire weekend.
The brunt of the first colder system pushes in early Friday morning
and snow levels will potentially be down to all valley floors from
the very beginning. While this storm will be quick-hitting and it
doesn`t have incredible QPF values, the high snow ratios associated
with the very cold temperatures could allow snow to pile up quickly.
We could see over a foot of snow above 7000 feet with a few inches
in the lower valleys of western Nevada and northeast California.
While there will be a brief break in between from Saturday afternoon
through Saturday night, snow showers could continue in the higher
Sierra. The next storm pushes in Sunday morning with another round
of snow for the Sierra and western Nevada. This second colder storm
appears stronger and more dynamic than the previous system, so we
could be looking at more significant snow accumulations across the
While these storms aren`t a guarantee since they are still 5-7 days
out, it is always good to be prepared. Stay stocked up on food,
water, and other supplies in case you need to stay at home for an
extended period of time, especially if you live above 6000 feet.
Also not a bad idea to keep those snow shovels and snow blowers
Areas of the low stratus deck have finally cleared today, giving us
a peek at the sun, but this clearing could mean trouble for the
lower valleys tonight. Areas of patchy freezing fog will be more
likely to develop in locations that become cloud free later this
afternoon and evening. KTRK will be the most likely location for
FZFG follower by KRNO and KCXP. KTVL and KMMH will have lower
chances of freezing fog developing but it is possible. Locations
that have freezing fog develop will be stuck with it from late
tonight through Tuesday morning.
Winds will remain relatively light for all terminals
through at least early Wednesday before another storm moves into the
region. By Wednesday an approaching storm system will allow winds
aloft to increase significantly with wind shear and turbulence
becoming a concern Wednesday. This storm will bring in high
elevation snow and rainfall to the lower valleys. -Edan
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