874
FXUS65 KREV 170906
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
106 AM PST Wed Dec 17 2025

.KEY MESSAGES...

* Gusty to strong winds will pose impacts to travel and recreation
  through this afternoon.

* Rain and high Sierra light snow showers will continue through
  this morning.

* A break on winds and precipitation is expected Thursday before
  wet and windy weather resumes Friday into the weekend, with
  potential for more atmospheric river events through Christmas
  Day.

&&

.DISCUSSION...

An upper shortwave trough continues to deliver light rain across
northern NV/CA this morning per radar and surface observations.
The higher chances of rain (60-90%) continue for the Tahoe Basin,
NE CA, and the Sierra Front through the morning. Snow levels
remain high, generally above 9 kft in the Sierra and 6-7.5 kft for
the Surprise Valley and northern Washoe, limiting significant
snow to the highest peaks. Precipitation will taper off by this
afternoon.

Winds remain the main concern through this afternoon. A deepening
surface low to our north, combined with robust 700 mb flow of
50-65 kts, will generate widespread gusty to strong winds. Wind
Advisories remain in effect for much of the area. The strongest
winds are anticipated in two periods: early Wednesday morning and
again late morning to early afternoon. SW/W gusts of 35-50 mph
across valleys, 50-70 mph in wind-prone areas, and 80-100 mph in
Sierra ridges are expected today. These winds will pose impacts to
travel and recreation, including aviation and crosswind hazards
on north to south oriented highways. Winds begin to weaken by this
evening.

Weak ridging returns on Thursday, resulting in mostly dry
conditions and significantly lighter winds. However, another
system approaches on Friday, bringing a return of gusty winds and
increasing chances for rain and high-elevation snow. NBM guidance
shows increasing precip chances for the Sierra and northern NV/CA,
though snow levels are expected to remain high initially and
decreasing by Saturday morning to 6-7.5 kft.

By Saturday, the deepening of an upper trough allows a westerly
to southwesterly flow into the West Coast conducive to a series of
atmospheric river (AR) events with rounds of precipitation to
Northern CA/NV. NBM guidance indicates high chances for
precipitation 60-90% across the Sierra and northern NV/CA through
early next week. Valley locations will also see increased chances
for rain 40-80%. While snow levels are expected to remain elevated
through much of the weekend, there is increasing confidence in
significant snowfall at higher elevations, above 7 kft, as colder
air eventually filters in.

The days leading up to Christmas still look favorable for
stronger winter storms, which may result in significant holiday
travel disruptions across the Sierra and western Nevada.
Confidence in the exact timing and intensity of these AR events
remains moderate, but the overall trend points to an active
pattern.

-HC

&&

.AVIATION...

Mountain wave turbulence and LLWS impacts will be the primary
concern for all terminals with light rain showers periodically
lowering CIGS/VIS to MVFR conditions at Tahoe and Sierra Front
terminals tonight through Wednesday morning.

SW/W FL100 winds continue at 40-60 kts through 18Z this morning.
Surface wind gusts SW/W reach 25-35 kts at KTRK-KTVL-KMMH and
35-45 kts at KRNO-KCXP-KMEV around 12Z. Mountain wave turbulence
and LLWS will likely be an issue to some extent through this
evening, but will be most intense from 12Z-18Z along with the
strongest winds.

Low clouds and occasional -RA/RA may obscure mountains for Sierra
and western NV terminals. Rain showers may sneak into KRNO- KCXP-
KMEV through 14Z.

-Salas/HC

&&

.REV Watches/Warnings/Advisories...
NV...Wind Advisory until 4 PM PST Wednesday NVZ002>005.

CA...Wind Advisory until 4 PM PST Wednesday CAZ070>072.

&&

$$