Lake Wind Advisory 51, NWS Reno, NV

920 
WWUS75 KREV 110246
NPWREV

URGENT - WEATHER MESSAGE
National Weather Service Reno NV
746 PM PDT Fri Sep 10 2021

CAZ072-NVZ002-110400-
/O.EXP.KREV.LW.Y.0051.000000T0000Z-210911T0300Z/
Greater Lake Tahoe Area-
Including the cities of South Lake Tahoe, Tahoe City, Truckee, 
Markleeville, Stateline, Glenbrook, and Incline Village
746 PM PDT Fri Sep 10 2021

...LAKE WIND ADVISORY WILL EXPIRE AT 8 PM PDT THIS EVENING FOR
LAKE TAHOE...

Winds are below advisory levels and will become light overnight.

$$

NVZ004-110400-
/O.EXP.KREV.LW.Y.0051.000000T0000Z-210911T0300Z/
Western Nevada Basin and Range including Pyramid Lake-
Including the cities of Fernley, Fallon, Lovelock, 
Silver Springs, Nixon, and Imlay
746 PM PDT Fri Sep 10 2021

...LAKE WIND ADVISORY WILL EXPIRE AT 8 PM PDT THIS EVENING FOR
PYRAMID LAKE...

Winds are below advisory levels and will become light overnight.

$$

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

Area Forecast Discussion
National Weather Service Reno NV
309 AM PDT Thu Sep 9 2021

.SYNOPSIS...

A low pressure system will bring increasing clouds, breezy winds,
and chances for showers and a few thunderstorms through Friday. A
dry and seasonably warm pattern will return over the weekend and
continue much of next week.

&&

.SHORT TERM...

No big adjustments were made this morning as a trough is still on
track to swing inland across northern CA and northwest NV through
Friday. The primary focus for storms continues to be overnight
into early Friday morning when the cold front and associated upper
level forcing will be best aligned.

STORMS: A few showers (more likely virga or sprinkles) were
making their way north across the northern Sierra early this
morning as moisture aloft increased from the south. Model
soundings are showing limited instability today with a lot of
cloud cover around. However, mid afternoon into early evening,
there should be enough instability to produce isolated storms,
most likely areas north of Susanville-Gerlach, and from the
Eastern Sierra of Mono County.

As the cold front approaches and forcing aloft increases tonight,
shower coverage will increase across the Sierra and western NV
with at least a low end chance for nocturnal storms (especially
between 200-800 AM). The better jet dynamics place the highest
risk for lightning over northeast CA and northwest NV, north of
Hwy 70 and Pyramid Lake. Storms will be moving fast, so most will
only put down brief QPF amounts up to 0.10". However, PWATs near
0.75" will allow for a few stronger cells to put down some locally
brief heavy rains (0.20-0.30"). All storms will be capable of
producing gusty outflow winds to 40 mph. Storms will wind down in
the afternoon and mostly be out of the region by sundown Friday.

WINDS: South winds will increase along the ridges today before
increasing dramatically this evening into the overnight hours and
persist Friday morning before gradually backing off during the
afternoon/evening. Ridge wind gusts will approach 80 mph tonight
and Friday morning with some of this momentum working down to the
valleys Friday behind the cold front, several hours with gusts
30-35 mph. These winds will likely impact any outdoor activities
including backcountry campers and boaters on area lakes.

SMOKE: Smoke impacts have decreased a bit with the diminished
fire activity from Caldor and Dixie. Expect smoke and reduced air
quality near these fires. Predictability and confidence in smoke
impacts elsewhere is low until we know how suppression efforts
over the last few days and this frontal system impact fire
activity.

Hohmann

.LONG TERM...Sunday and beyond...

The close of the weekend will see a more progressive pattern set up
over the PacNW with higher pressure still exerting its dominating
presence over the desert southwest. A weak ridge will push north
into the Great Basin region and increase the likelihood of continued
dry conditions with no foreseeable chances of precipitation until
further notice. Model simulations are showing better confidence for
an upper short wave darting over the region later Sunday into Monday
but a brief period of gusty conditions over the Sierra crest Sunday
afternoon should be the only tell-tale sign of its passage. A brief
period of more northwesterly upper winds will follow and ensure
temperatures remain nearer to seasonal averages. As the upper
pattern begins to rebound more from the southwest on Tuesday, expect
those more typical afternoon breezes to begin once more over the
eastern Sierra and drift into the basin areas of western NV.
Ensemble guidance aligns well with this scenario through mid-week.
Into the latter half of next week, model guidance begins to falter
and increases the uncertainty through the remainder of the long term
period. But some simulations are hinting at a pattern change going
into next weekend so stand by for further details. :0 -Amanda

&&

.AVIATION...

VFR conditions expected to continue except for downwind of wildfires
and near any showers or thunderstorms. KTVL downwind of the
Caldor Fire and KSVE downwind of the Dixie Fire will be most
likely to see MVFR/IFR CIG/VIS as winds remain out of the
southwest to west through the weekend. Increasing mid-level clouds
along the eastern Sierra ridges and lee-sides today with the
approaching trough, with cu potential increasing this afternoon
into overnight. There are 10-20% chances for showers or
thunderstorms for Sierra and western NV terminals this afternoon
through Friday, with higher chances north of I-80 tonight into
Friday morning. Brief IFR conditions in heavy rain and outflow
winds around 35 kts are possible near any thunderstorms.

Plan on typical afternoon gusts at the terminals around 20-25kt
today, with increasing gusts 25-30kt tonight into Friday. Expect
areas of moderate turbulence beginning tonight along and east of the
Sierra as an upper level trough approaches. Improving chances for
LLWS and turbulence mixing down to terminals during the day on
Friday with gusts reaching 30-35kts. JCM

&&

.FIRE WEATHER...

...FIRE WEATHER WATCH ISSUED LATE THIS EVENING THROUGH FRIDAY...

* Thunderstorms possible through Friday, including nocturnal
  storms overnight into Friday morning.

* Gusty Winds Expected Friday with a Cold Frontal passage.

An incoming low pressure system will provide multiple impacts which
will likely result in critical fire weather conditions late today
into Friday across NE California and the Tahoe Basin.

Thunderstorms:

* The first line of impacts looks to be high based thunderstorms
  beginning this afternoon. Development looks to favor from
  southern Mono County through far western Nevada including the
  Sierra Front. While not strongly forced and likely not big
  lightning producers, they will however be fast moving with the
  potential to produce gusty outflow winds tracking south to
  north.

* The main threat for dry lightning strikes will be tonight into
  Friday morning as stronger forcing arrives with a jet streak
  pushing across Lassen County through the Tahoe Basin. Very fast
  storm motions which could limit chances for wetting rains.
  Initial timing could bring banded convection across Lassen and
  Plumas counties as early as 2-3am Friday and across the Tahoe
  Basin after 3-4am. Only medium confidence on timing but will
  continue to monitor CAM and ensemble trends.

* Thunderstorm activity should wane behind the frontal passage which
  looks to be early-mid morning Friday across Lassen and Plumas
  counties and mid-afternoon across the Tahoe Basin. Gusty outflow
  winds from any storms could affect both the Dixie and Caldor
  wildfires. As the west winds develop in the afternoon, some storms
  may develop into western Nevada.

Winds:

* Gusty southwest winds will be the next impact behind the cold
  frontal passage. Winds across mountain ridgetops will be first
  to begin to feel wind tonight with gusts of 50+ mph
  materializing and persisting through Friday evening. Elevated
  winds across elevated midslopes are also possible with continued
  poor humidity recovery.

* These winds will begin to mix down through the day as the cold
  front sweeps through the region. Overall, southwest wind gusts of
  30-35 mph are expected with up to around 40 mph possible along the
  cold front and across wind prone locations.

* While humidity will increase due to the passing cold front,
  minimum RH will still be in the 15-20% range for lower valleys and
  20-25% range in Sierra valleys. Even with the marginal humidity,
  it won't be much of a limiting factor when we consider the
  forecast wind speeds for Friday along with the ongoing extreme
  dry nature of the fuels across the Sierra.

As such, Fire Weather Watches have been posted from the Tahoe Basin
through NE California including the Dixie and Caldor wildfires.
These areas will see the best of potential of dry lightning strikes
and storm outflows followed by gusty winds during the day Friday.

Areas across far northern Washoe County could see thunderstorm
potential but also higher chances for wetting rains. Other areas
of western Nevada will see gusty wind potential but also increased
humidity which may lead to more along the lines of isolated areas
of critical fire weather conditions. Fuentes

&&

.REV Watches/Warnings/Advisories...
NV...None.
CA...Fire Weather Watch from this evening through Friday evening
     CAZ271-272-278.

&&

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