Coleville, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

118
FXUS65 KREV 211202
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
402 AM PST Sun Dec 21 2025

.KEY MESSAGES...

* Heavy rains that could lead to localized flooding, strong to
  damaging winds, and heavy wet snow in the Sierra above 8000
  feet are all in the forecast for the region today going into
  tomorrow.

* Following the beginning week system, a brief lull in precipitation
  is seen on during the day on Tuesday with gusty ridge winds.

* Another round of stormy conditions could bring significant rain
  and snow along with enhanced winds late Tuesday through Christmas
  Day, but confidence in the details remains mixed.

&&

.DISCUSSION...

Today and Monday: Current radar returns shows rain continuing to
fall this morning in northeastern CA and the Tahoe Region with
some snow mixed in at the higher elevations in the Sierra. This
ongoing system expects bringing a trio of weather concerns to the
region for the beginning of the week, so I`ll try to break them
down as best as I can:

1) Heavy rain that could cause potential flooding: a Flood Watch
continues for northeastern CA and the Tahoe region through Monday
afternoon. In their latest Excessive Rainfall Outlook, the WPC has
recently highlighted a slight risk (at least a 15% chance of
excessive rainfall) within the CWA for areas generally along and
west of a line from Bieber-Susanville-Truckee-South Lake Tahoe in
CA. It`s also worth noting that the WPC has an area of moderate
risk (at least a 45% chance) near and west of Donner going over
the summit with a marginal risk (at least 5% chance) going to the
CA state border in northeastern CA and the Tahoe region. Within
the slight risk areas, the latest NBM probabilities give a 60-80%
chance for a 2-day QPF total of 2+ inches with the moderate risk
areas seeing 70-80% chance of 3+ inches due to this system being
an atmospheric river event pumping in a generous amount of
moisture. For more information on potential impacts this
rainfall could have: please see the Hydrology section below.
Please use caution if you have to drive through these hazardous
conditions today and tomorrow as amongst the potential flooding
impacts, visibilities can be reduced due to increased rainfall
intensity. Elsewhere, Sierra Front communities can expect light
rain chances through tomorrow with showers reaching down into Mono
county. The NV Basin and Range see lesser chances for rain (<15%).


2) Heavy, wet snow above 8000 feet in the Sierra: Snow levels are
forecast to drop down to around 8-8.5 kft by the late
afternoon/evening hours which will turn P-type to snow that
continues into Monday. Please see weather.gov/winter for more
details including forecast snowfall totals and the Winter Weather
Advisory issued for the Greater Lake Tahoe area and Mono County as
accumulating snow causing impacts is expected in these portions
of the CWA above 8000 feet. SLRs do continue to look to be 5-8:1,
so snow will be wetter and slushier. Some snow may also mix into
the rain down to areas with elevations around 7000 feet as well,
so please keep this in mind if traveling through area as roads
will be slick. Increased winds may also cause some blowing snow
which could lower visibilities as well.

3) Strong to damaging winds: Forecast guidance is still showing a
700 mb jet over the CWA with winds up to 75 knots which will allow
ridgetop gusts of at least 100 mph and valley gusts upwards of 50-65
mph through tonight within the CWA. Please refer to the High Wind
Warning, the Wind Advisories and the Lake Wind Advisory for
Pyramid Lake for more details on the wind concerns in your area.
The latest NBM probabilities for damaging wind gusts (60+ mph)
today still look to be around 50% for Reno-Carson City-Minden area
down towards Mono County with wind prone areas having around a
50-60% chance of wind gusts of 70+ mph. These strong to damaging
winds will bring difficult travel for high profile vehicles, bumpy
flights, and recreational concerns amongst other impacts. Please
secure your outdoor holiday decorations now if you have not
already!

Tuesday: There looks to be a brief break on Tuesday from impactful
weather as models show the precipitation tapering off late Monday.
While there could still be some lingering precipitation chances in
the Sierra on Tuesday, showers look to be lighter in nature with not
much QPF expected. If you are targeting a time for necessary holiday
travel across the Sierra, Tuesday morning and afternoon currently
look to be the best chance (though there could be some lingering
impacts from the system at the beginning of the week). One thing
to consider though is that ridgetop winds expect to still be a
bit gusty with the NBM showing a 50-60% probability of 60+ mph
gusts on Tuesday. But by Tuesday evening going into the night, the
next impactful weather system begins to move into the region which
will close the potential window for "better" travel conditions.
Forecast guidance shows western NV staying mostly dry throughout
Tuesday.

Wednesday through Friday: Confidence is improving as the Christmas
holiday grows closer that an impactful winter weather system will be
affecting the region particularly in the Sierra and northeastern CA.
As such, a Winter Storm Watch has been issued for these areas
starting late Tuesday night through Friday afternoon. The WPC is
particularly highlighting the Sierra for potential heavy snow in
their medium range hazard forecast. There seems to be good
confidence that the snowfall amounts in the aforementioned areas
over these three days may be measured in feet instead of inches
as there currently is a 60-70% NBM probability for over 1 foot of
snow in the Tahoe Basin at lake level by Friday afternoon. Snow
levels look to be around 5.5-6.5 kft on Wednesday and reach down
to around 5-6 kft by Friday morning. Aside from the wintry
precipitation, the system could allow for the Sierra ridgetop
winds to gust up to around 100 mph once again. Across the CA/NV
border, the Reno-Sparks metro area currently has a 20-30% NBM
probability of at least 1 inch of snow by Friday afternoon so the
valleys may even have a chance for measurable snow. There is also
some potential for effects of the upcoming system to continue into
the weekend. Exact details on timing and precipitation amounts
with this system are still uncertain, so please watch for forecast
updates as travel across the Sierra could potentially be
difficult to impossible. -078


&&

.AVIATION...

An impactful atmospheric river system will bring in rainfall chances
today across the region that could be moderate to heavy at times
from Alpine County north through Lassen County including in the
Greater Lake Tahoe area. As the intensity of this precipitation
increases, KTRK/KTVL will see visibilities decrease to IFR/LIFR
levels later today. NV TAF sites may occasionally drop to MVFR
visibility when rain occurs. Higher elevations in the Sierra may
see snow as the P-type today while KTVL could see a rain/snow mix
tonight. Area-wide LLWS, surface winds up to around 40-50 kts,
and ridgetop winds gusting up to 100 mph are also to be expected
today on account of this system which will cause additional aviation
impacts. Effects of this wintry system look to continue into tomorrow
before tapering off overnight going into Tuesday. -078

&&

.HYDROLOGY...

Moderate to heavy rains will lead to significant rises on rivers and
streams today into Monday most notably from Alpine County north
through Lassen County.

Minor flooding of small streams, urban and poor drainage areas and
rockfall in steep terrain are possible during any prolonged periods
of high intensity rainfall.

While no mainstem river flooding is currently forecast, the Susan
River near Susanville and the West Fork of the Carson near Woodfords
are currently expected to exceed action stage and minor flooding can
not be ruled out in these area. Additionally, the latest forecast
shows the Susan River approaching minor flood stage as early as
Sunday afternoon. Remain aware of the potential for additional river
and stream rises near Christmas Eve in large mountain drainages
below about 6000 feet like the Susan River. In these areas
additional rain and saturated conditions could lead to fast rises
and renewed flooding concerns. In other areas, lowering snow levels
will reduce flooding concerns into next week.

Enhanced runoff and sediment transport are likely below recent burn
areas, but debris flows are not expected. Watch for additional rises
near Christmas Eve and possible flooding concerns especially in
drainages with large mountain drainages below about 6,000 feet, like
the Susan River for example.

You can find river forecasts updated twice daily at:
www.cnrfc.noaa.gov

-Tim/Giralte

&&

.REV Watches/Warnings/Advisories...
NV...Flood Watch through Monday afternoon NVZ002.

     Wind Advisory until 4 AM PST Monday NVZ001.

     Winter Storm Watch from Tuesday evening through Friday morning
     NVZ002.

     Wind Advisory until 4 AM PST Monday NVZ002.

     Winter Weather Advisory from 4 PM this afternoon to 1 PM PST
     Monday NVZ002.

     High Wind Warning until 4 AM PST Monday NVZ003.

     Lake Wind Advisory until 4 AM PST Monday NVZ004.

CA...Flood Watch through Monday afternoon CAZ071-072.

     Wind Advisory until 4 AM PST Monday CAZ071.

     Winter Storm Watch from Tuesday evening through Friday morning
     CAZ071>073.

     Wind Advisory until 4 AM PST Monday CAZ072.

     Winter Weather Advisory from 4 PM this afternoon to 1 PM PST
     Monday CAZ072-073.

     High Wind Warning until 4 AM PST Monday CAZ073.

&&

$$