Area Forecast Discussion
Issued by NWS Reno, NV

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
214
FXUS65 KREV 190154 AAA
AFDREV

Area Forecast Discussion...UPDATED
National Weather Service Reno NV
554 PM PST Sun Feb 18 2018

.UPDATE...

The cold front and associated band of snow has already dropped 2-3
inches in the north valleys with web cams along the I-80 corridor
indicating snow sticking to roads and poor visibility within this
band from the Tahoe Basin all the way to Lovelock. The snow will
end from north to south this evening but with very cold
temperatures filtering into the area, roads will either remain
snowpacked or slush/water will flash freeze and produce very slick
driving conditions this evening. A winter weather advisory has
been issued for the entire I-80 and Highway 50 corridors through
the Tahoe Basin and western NV through 10 pm although slick
conditions will likely persist overnight into Monday morning where
roads are untreated. Hohmann

&&

.PREVIOUS DISCUSSION... /Issued 117 PM PST Sun Feb 18 2018/

SHORT TERM...

Bottom line up front: It will be bitterly cold the next couple of
days with hazardous wind chills and snow showers through Monday.

Cold front is pushing through the region this afternoon bringing
gusty winds, snow showers, and the start of the coldest temperatures
we have seen so far this season. Showers have already begun in
northeast California with high resolution guidance showing the band
moving through the Tahoe Basin and greater Reno/Sparks/Carson City
metro areas between 3 pm and 7 pm. It will be just an hour or so
later for the west central Nevada basin and range, then this evening
for Mono/Mineral counties. Snow levels will come crashing down
behind the front, with profilers in northern California already
showing snow levels around 2500 feet and falling. Snow levels by
Monday morning will only be a couple hundred feet above sea level --
well below anything here in the eastern Sierra or western Nevada,
but indicative of just how cold this airmass is.

Despite the incoming cold, there is a decent chance that the snow
showers this afternoon and evening may melt due to the heat stored
in the ground with the recent warmth. This brings the potential for
a flash freeze tonight anywhere liquid remains on surfaces. It`s a
bit of a mixed bag because there won`t be a huge amount of liquid
equivalent and the dry air mass ahead of the front along with the
wind will help to rapidly evaporate what is on the ground. We can
say the potential is there, however, it is nearly impossible to
determine exactly where this will and won`t set up. Just keep in
mind that roads are likely to be slippery in spots tonight into
Monday morning.

Lake effect snow bands are possible on the southern end of Tahoe and
Pyramid Monday morning through late afternoon. There is decent
unidirectional flow from the north and an extremely cold air mass
moving over the relatively warm lake waters. This may lead to
localized banding of heavier snow totals. Chances diminish Monday
evening as winds shift and weaken.

Gusty northwest winds combined with frigid temperatures will make
wind chills a concern tonight through Monday. Wind chills will be
dangerous on exposed high mountains overnight into Monday morning
with apparent temperatures in the -10 to -25 degrees F range. In
addition to the wind and cold, scattered snow showers are also
possible through the day Monday under the cold, unstable core of the
low.

The cold weather will continue into Tuesday with high temperatures
only reaching a bit above freezing even in warmest valleys. The good
news is winds will be light so it won`t feel quite as cold as
Monday. Low temperatures Tuesday and Wednesday mornings will be in
the teens in the warmest locations with single digits and below zero
likely in colder valleys. -Dawn

LONG TERM...Wednesday through next week...

The West will remain beneath a cold trough for much of the
extended which will maintain below normal temperatures as well as
increased potential for precipitation. Multiple cold shortwaves
are forecast to drop through the base of the trough and reinforce
the cold air across the Sierra and western Nevada through the end
of this week and into early next week.

The next storm will drop through on Thursday bringing another round
of snow for the Sierra and down into the valleys of western Nevada
and northeastern California as well. Plan on travel delays and
impacts due to snow in the Sierra and possible the evening commute
in western Nevada.

Additional storms progged to drop into the Sierra and western Nevada
for next weekend and early next week as well. While none of these
storms will have a significant moisture tap associated with them,
they will bring reinforcing shots of cold arctic air as well as
chances for precipitation and winds.

Travel plans late this week into next week? Keep an eye on the
forecast discussion and the evolving forecast since the weather
pattern will remain active through the end of February and into
early March. -Edan

AVIATION...

Strong and gusty winds continue area-wide, but are beginning to
subside north of approximately Highway 50 from their peak earlier
today. KMMH is likely to still see high winds through this evening
until the cold front pushes through the region tonight. Mountain
wave activity and turbulence continues, along with shear possible
along the cold frontal boundary. Low level wind shear does not appear
to be as much of a concern as upper and lower level winds are in
better alignment, outside of KTVL where the terrain influences bring
LLWS potential. Northwest winds will remain breezy tonight into
Monday, with peak gusts 15-20 kts.

There will be a quick burst of snow just behind the cold front with
the most likely timing for KRNO, KCXP, KTVL, and KTRK between 22-
02z. Scattered showers will continue overnight into Monday, but
these will be much more spotty. 2-4" of accumulation looks possible
for the Tahoe Basin sites and up to 1" for western Nevada valley
sites. Farther south, KMMH is likely to see more showery conditions
with the front weakening as it moves south, with up to an inch
possible overnight.

It will remain cold, but otherwise flying conditions will be much
more pleasant for Tuesday. -Dawn

&&

.REV Watches/Warnings/Advisories...
NV...Winter Weather Advisory until 10 PM PST this evening NVZ002>004.

     Wind Advisory until 10 PM PST this evening NVZ001.

CA...Winter Weather Advisory until 10 PM PST this evening CAZ072.

     Wind Advisory until 10 PM PST this evening CAZ073.

&&

$$

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.