High Wind in Nevada, April 18 to 19, 2022

Area Forecast Discussion
National Weather Service Reno NV
217 PM PDT Mon Apr 18 2022

.SYNOPSIS...

Additional April storms are expected this week bringing gusty
winds, rain, and mountain snow. The first system today and
Tuesday will be more of a wind producer, with snow impacts mostly
confined to higher passes in the Tahoe Basin. A second storm late
Wednesday to Friday looks to be colder and wetter with more
widespread impacts. Warmer and drier weather returns next
weekend.

&&

.SHORT TERM (Through Tuesday Night)...

Not much to add to the previous forecast as gusty winds continue to
mix down into the Sierra and western NV today. As the incoming
cold front presses across northern CA, snow showers will follow
into the Sierra and bring travel impacts to Tahoe area mountain
passes overnight into Tuesday morning.

* Winds remain the primary focus point going into the evening
  hours. Winds across the higher Sierra ridges are now gusting
  60-75 mph with wind gusts over most areas across western NV
  increasing to 30- 40 mph. Blended ensemble guidance shows these
  higher end gusty conditions continuing across the region through
  Tuesday morning. Current 700 hPa Hi-Res model guidance continues
  to bring in winds ranging 45-60kt over the Sierra and western N.
  This presses the notion of wind gusts reaching 100+ mph across
  Sierra ridge-tops for a good part of this forecast period. Lower
  elevation areas could still see sustained winds ranging 20-30
  mph with potential gusts to 50 mph. Wind prone spots along the
  395/I-580 corridor may still exceed 60 mph later this evening
  into Tuesday morning when the core of strongest winds shifts
  further southward into the eastern Sierra.

* Mountain and lake recreation, high profile vehicle, and aviation
  impacts can be anticipated across the Sierra and western NV
  through this event. Expect areas of blowing dust north of
  US-50, particularly downwind of sinks and dry lake beds. With
  the rather dry conditions going into the evening, combined with
  strong/gusty winds, please be mindful with open flames or
  anything that can cause sparks. No major changes were noted at
  this time for the current wind and lake wind advisories.

* With the continued gusty winds, a cold front will briskly move
  into the Sierra, spreading showers first across Lassen and
  Plumas Counties, then continuing south into the Lake Tahoe
  Basin. Blended QPF values ranging 0.65 to nearly an inch over
  higher mountain areas will only reach into a few hundredths of
  an inch across far western NV with the remainder of western
  Nevada being rain-shadowed for this storm. Snow levels should
  remain around 6,000-6,500 feet with snow impacts starting over
  northern Sierra passes late Monday night (10PM- 12AM) and
  shifting into the eastern slopes of the Sierra shortly after
  midnight

* Snowfall totals look to be 4 to 12 inches for areas west of
  Highway 89, including Donner Summit with 4-7 inches over Echo
  pass along US-50. Two inches or less can still be expected in
  the Tahoe Basin and surrounding Sierra communities below 6,500
  feet, i.e. South Lake Tahoe, Truckee, Incline Village, etc.
  Snow should then quickly move on with the exiting cold front
  with related improvements in road conditions. A Winter Weather
  Advisory remains in effect through 11AM Tuesday for locations
  above 6,500 feet. Impacts outside of these passes are still
  possible, but will generally be minimal or short lived for this
  storm. -Amanda

.LONG TERM...Thursday Onward...

The next storm for Wednesday into Friday will be more impactful than
the latest one. Widespread gusty winds along with rain/snow will
result in difficult travel conditions from Thursday into Friday. No
significant changes to the ongoing forecast.

Winds: Winds will ramp up on Wednesday with the peak winds for
Thursday morning. With wind gusts 35 to 50 mph, there will be
widespread impacts to travel (air & ground) and recreation (lakes,
backcountry, and ski areas) from Wednesday to Thursday. As the cold
front drops southward Wednesday night, the winds will remain
elevated and then the strongest winds will migrate south into the
Eastern Sierra of Mono County and eastward to Mineral County
Thursday. Sierra ridge winds may stay quite gusty from this storm
into the Wednesday storm, with only a short break from late Tuesday
afternoon into early Wednesday. Forecast ridge gusts around 100 mph
(again). By Friday, the winds will drop off, but a brisk northwest
flow will remain across the region.

Rain/Snow: Snow levels with this storm will be substantially lower
than previous system with simulations pegging them around 5500 feet
by early Thursday morning. Timing looks about the same for the snow
onset with snow pushing into western Lassen county Wednesday
afternoon and then spreading southward to the Tahoe Basin overnight
into Thursday morning. Snow potential will progress to the rest of
the Sierra during the day Thursday with the cold frontal passage.
The best potential for spillover into western Nevada will be on
Thursday where jet dynamics and forcing with the front align. During
this time, conditions will rapidly deteriorate in the higher
elevations. Plan for elevated snowfall rates in the Sierra and the
potential for convective snow showers that would produce rapid
accumulations and limited visibility. The best potential for
convective activity will be just west of the crest, but we cannot
rule out a thunderstorm or two for the Sierra and the Tahoe Basin.

Blended model guidance shows a 30% chance of >24" of snow for along
the highest Sierra crest, above 8000 feet. The convective snow bands
would boost the likelihood of the amounts approaching 3 feet for the
highest terrain. Otherwise, there is a 80% chance of at least 6" of
snow impacting the Tahoe Basin, as well as Yuba Pass and Fredonyer
Summit. Along Highway 395 in eastern Mono County, the potential for
several inches of snow and up to 6 inches along the higher pass will
create travel issues. For lower elevations below 5000 feet the
probabilities for snow accumulating fall off, but aren't zero
percent chances. Blended model guidance indicates a 30% chance of at
least an inch of snow in Reno and a 60% chance for Carson City. For
the Basin and Range, the snow potential really drops off.

Travel through the Sierra and northeast CA will be obnoxious with
the snow in the forecast, especially from Wednesday night and
Thursday. Lingering travel impacts may persist into Friday morning
as well.

Dry and mild weather will prevail for the weekend, but there is
still some potential for more weaker systems next week.
-Edan

&&

.AVIATION...
VFR conditions should prevail for all terminals into evening. Sierra
terminals will be the first to see reduced conditions overnight into
Tuesday morning as precipitation moves into the Sierra and snow
levels fall to near airport level.

Snow accumulations at Sierra terminals should be minimal as snow
showers work their way into the region after 06Z. Western NV
terminals (KRNO-KCXP-KMEV) will see periods of MVFR/IFR as some
spillover showers moves into region between 09-12Z.

* KTRK will see VIS/CIG lowering to MVFR in -RASN after 06Z with
  alternating periods of IFR in moderate mix of RN/SN or SN between
  09-15Z.

* KTVL will start with MVFR conditions for VIS/CIG after 06Z as -SN
  could   bring snow accumulations up to an inch through Tues
  morning. Periods of moderate SN/SHSN are possible at KTVL between
  09-15Z that will bring brief periods of IFR/LIFR conditions before
  transitioning to -RASN after 15Z.

LLWS will continue to impact Sierra terminals through Tuesday as
increasing surface winds and gusts will impact all eastern CA and
western NV airports through the overnight hours. Brief periods of
MDT-SVR turbulence will accompany the increase in winds over Sierra
terminals, which will propagate east over far western NV terminals.
By 03Z Tuesday, LLWS will spread to the lee side of the Sierra and
impact RNO/CXP/MEV/MMH through Tuesday. Blowing dust may restrict
visibility later this afternoon near and east of Lovelock and
Fallon.

-Amanda

&&

.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory until 8 AM PDT Tuesday for Pyramid Lake in
     NVZ004.

     Winter Weather Advisory from 2 AM to 11 AM PDT Tuesday above
     6500 feet in NVZ002.

     Wind Advisory until 11 AM PDT Tuesday NVZ003-005.

     Lake Wind Advisory until 11 AM PDT Tuesday for Lake Tahoe in
     NVZ002.

CA...Winter Weather Advisory from 2 AM to 11 AM PDT Tuesday above
     6500 feet in CAZ072.

     Wind Advisory until 11 AM PDT Tuesday CAZ070-071-073.

     Lake Wind Advisory until 11 AM PDT Tuesday for Lake Tahoe in
     CAZ072.

&&

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