Mount Shasta, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

157
FXUS66 KMFR 170649
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1049 PM PST Mon Feb 16 2026

.DISCUSSION...The main update this evening was to upgrade to a
Freeze Warning /PDXNPWMFR/ for the coast Late Tuesday night into
Wednesday morning. It will be cold across the area, but freezing
temperatures at the coast could affect sensitive vegetation. It
will also be almost as cold on Tuesday, Thursday, and Friday
mornings, but likely just shy of freezing on those mornings for
the coast. Friday has the best chance for a future suite of data
to trend slightly colder and warrant another Freeze Warning for
the same area.

While the forecast hasn`t changed, the focus remains on low snow
levels with Winter Storm Warnings or Winter Weather Advisories in
effect from the Coast Range eastward from now through Thursday
morning, then tapering off into Thursday night. South to southwest
winds will be gusty at times during this event, but mainly at 15
to 30 mph.

The main bursts of snow will be from now into Tuesday evening,
and Wednesday evening through Thursday morning...except lingering
into Thursday evening for Lake and Modoc counties. In between, on
Wednesday, expect isolated to numerous light snow flurries and
snow showers, mostly over the higher terrain.

For Roseburg, while not during the wettest period, the highest
probability of snow will be due to the arrival of a colder air
mass late Tuesday night into early Wednesday, with a trace to
around a half of an inch of snow possible. Grants Pass, and
downtown Medford will also have their coldest temperatures early
Wednesday, coinciding with an isolated level of snow shower
activity.

Elsewhere from the Coast Range inland, this will be a couple of
all-snow events. Terrain influences west of the Cascades will
have a significant effect on snow levels, with a substantial
accumulation of a few inches for the I-5 passes on the Umpqua
Divide/northern Josephine County, and also a few to several inches
from Hayes Hill to Cave Junction. The forecast of snow amounts
is a greater challenge than usual given warm soils and
(particularly) roadways that will delay the start of
accumulation. When all is said and done on Thursday night, up to
an inch is expected for most of the Umpqua Valley, 2 to 6 inches
for the Camas, Rogue, Applegate, Shasta, and Scott valleys and
also east side valleys. Higher amounts of 6 to 12 inches are
expected for southwest Josephine County, and western and southern
Siskiyou County. Meantime, the higher terrain across the area is
expected to receive 1 to 2 feet.

A mostly dry break is possible Friday through Saturday, with a
noteworthy minority of ensemble members that are stronger with a
weak front, and/or closer to shore with the following slow
moving, wet cold front on Saturday/Saturday night.

Snow levels will be higher but preciptation amounts could again be
substantial with this front as it tracks inland early next week.

&&

.AVIATION...17/06Z TAFS...Bands of showers and some lower MVFR and
IFR ceilings are moving across the area this evening, and will
continue through tonight.

Colder air is settling into the area and some of the terminals will
have a good chance of snow showers later tonight into Tuesday
morning. Medford(KMFR) usually underperforms under a shower pattern
with westerly flow, although a short wave will enhance things
tonight. Freezing levels will bottom out around 1300 feet, so it
will definitely be cold enough for accumulating snow, and
visibilities will likely suffer in any heavier snow showers.

Look for IFR and LIFR conditions later tonight as this next short
wave moves through and produces snow and lower ceilings at many of
the terminals. Some very slight improvement is expected through the
day Tuesday, but showers and areas of MVFR will continue.

-Smith

&&

.MARINE...Updated 800 PM PST Monday, February 16, 2026...Steep seas
continue this evening. We`ll see seas move even higher by Tuesday as
wave heights approach 16 feet in the outer waters due to an
increasing westerly to northwester swell. These conditions will
remain hazardous to smaller crafts through Wednesday. The weather
pattern will keep this northwesterly swell and breezy northwesterly
winds into Thursday.

Eventually, a low will likely deepen in the eastern Pacific around
140W. Models are bringing some strong southerly winds to our waters
with Gale force winds a threat for the region.

-Smith

&&

.PREV DISCUSSION... /Issued 233 PM PST Mon Feb 16 2026/

Note: Please see previous discussion below for further details.

Key Points:

* Snow: Widepsread Minor to Moderate Impacts Today-Thurs night
    - Moderate to heavy snowfall for mountains/passes
    - Snow levels dropping each day
        - Down to 500ft - 1000ft Tues & Wed mornings
        - Light amounts (Trace-1.0") for valley floors
    - Heaviest amounts for western Siskiyou, Mt Shasta area,
      Cascades, and Kalmiopsis Wilderness

* Rainfall: Minor Impacts
    - Continues through late this week
    - Not expecting widespread flooding but roads could be hazardous

* Wind
- Combination of wind & snow could further disrupt travel by
      reducing visibilities
    - Breezy to gusty winds across northern California and eastside
    - Breezy winds also possible for some westside areas

-Guerrero

PREV DISCUSSION... /Issued 1117 AM PST Mon Feb 16 2026/

With an upper trough looking to stay in place over the western
United States, active wintry weather is expected through most of
the upcoming week. Conditions today do look to stay relatively
unimpactful but worsen overnight. A low pressure system that was
bringing precipitation to northern California weakens and another
low approaches the area from the north. Both of these systems will
bring precipitation through the day across northern California
and southern Oregon, but nothing hazardous for most areas. A
Winter Storm Warning remains in place for areas in Siskiyou County
over 5000 feet, where moderate to heavy snowfall is expected.
Snow levels look to stay at 3500-4500 feet through the morning. As
the system from the north approaches, snow levels will start to
drop for areas west of the Cascades. West of the Cascades, light
snowfall is expected to stay over terrain through today. The
Cascades themselves and the Warner Mountains in Modoc County will
see significant snowfall of 5 to 10 inches today, and lower
elevation areas east of the Cascades look to see fractions of an
inch of snowfall.

The low pressure system to the north moves over the area on Tuesday,
bringing a cold air mass as well as abundant precipitation across
the area. Westerly flow aloft will focus activity over western
Siskiyou COunty and the Cascades. By early Tuesday morning, snow
levels west of the Cascades look to lower to 500-1000 feet,
bringing the possibility of snowfall to west side valley floors.
For the west side, the most activity looks to take place through
the morning. The Mount Shasta region (Mount Shasta City, Dunsmuir,
Weed) and areas east of the Cascades will see more activity in
the late afternoon and evening. With the exception of the Umpqua
Valley, area valleys and basins may see 1 to 2 inches of snowfall.
Lingering surface warming and moisture will help to prevent
immediate accumulation in these areas, but roadways may be locally
slick where slush is present. 5 to 12 inches of snowfall is
expected over the Cascades, with 12 to 24 inches forecast over
terrain in western Siskiyou County.

With low snow levels and precipitation continuing through the day,
Winter Storm Warnings are in place for areas at 1500 feet or higher
west of the Cascades. This Warning is meant to highlight the chance
of dangerous conditions while traveling over area passes. A Winter
Storm Warning also remains in place for areas in western Siskiyou
County and in the Mount Shasta region for continuing snowfall. All
other areas have a Winter Weather Advisory in place starting Tuesday
morning.

The cold air mass lingers on Wednesday but precipitation becomes
more showery and intermittent across the area. Snowfall remains in
the forecast for elevated terrain, while valley floors may see an
occasional snow shower. One recent addition to the suite of winter
hazards is a Freeze Watch for coastal areas early Wednesday morning.
Additional information on how the cold air mass looks to behave will
help to determine if an upgrade to a Freeze Warning will be needed.

Another round of possibly impactful activity is possible on Thursday
as another low pressure system looks to slide into the upper trough
and swing over the area. Some questions on timing and snow levels in
this timeframe remain, and the path of the low could change the
expected impacts as well. Please stay tuned for any updates on the
forecast as winter weather looks to continue towards the end of the
week and possibly into the upcoming weekend.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Winter Storm Warning until 10 AM PST Thursday for ORZ023-024-
     026.

     Winter Weather Advisory from 4 AM Tuesday to 10 AM PST Thursday
     for ORZ023>031.

     Freeze Warning from midnight Tuesday night to 9 AM PST Wednesday
     for ORZ021-022.

CA...Winter Storm Warning until 10 AM PST Thursday for CAZ080-082-
     083.

     Winter Weather Advisory from 4 AM Tuesday to 10 AM PST Thursday
     for CAZ081-084-085.

PACIFIC COASTAL WATERS...Small Craft Advisory until 4 PM PST
     Wednesday for PZZ350-356-370-376.

&&

$$