Ice Storm in Washington, February 12 to 13, 2021

Name: Ice Storm in Washington, February 12 to 13, 2021
Start: 2021-02-12T00:00
End: 2021-02-13T07:00
Location: Washington

February 12 to 13, 2021 · NWS SEW · 1 event in 1 county or zone

A significant winter storm impacted all of Western Washington during the overnight period on February 12 and continuing through the morning hours of February 13. While most of the Washington lowlands experienced significant snowfall, the Washington Coast experienced freezing rain and ice accumulation as a layer of warmer air over spread the very cold arctic airmass at the surface.

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS SEW wrote it up.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Seattle, WA wrote its last area forecast discussion before the first event at Feb 11, 8:11 PM PST, 3 hours 49 minutes earlier.

Area forecast discussion, Feb 11, 8:11 PM PST, 3 hours 49 minutes before

Area Forecast Discussion
National Weather Service Seattle WA
811 PM PST Thu Feb 11 2021

.UPDATE /THIS EVENING/...Forecast largely on track for this
evening so haven't made major updates to the near-term forecast.
Light snow continues across the Olympic Peninsula and near and
south of the Snohomish/King county border. Heaviest accumulations
have been found across the southern Sound with amounts so far in
the 3 to 6 inch range. Little to no accumulation on the northern
fringe of the snow shield. Light snow will continue in this area
into Friday morning - latest hi-res guidance in decent agreement
on northward extent as well. Entire forecast package will be
updated overnight. Previous discussion follows with updates to the
aviation and marine sections below. Carpenter

&&

.SYNOPSIS...Wintry weather will continue across western Washington
this weekend with the first system affecting the region tonight. A
second and likely more impactful system is on track to arrive
Friday night, lasting into Saturday and providing widespread
snowfall to western Washington. Temperatures may rebound into
early next week, but the unsettled pattern is likely to remain.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...Wintry weather will
continue across western WA through the weekend with more lowland
snow on its way, and likely impacts across the region.

First up, we're in the midst of storm number 1 which will mostly
affect areas around the south sound to Lewis county. Cams have
been showing snowflakes falling all day but not much is
accumulating yet (but will likely do so overnight as temps fall).
We're still looking for total snowfall amounts up to 4 inches
overnight. The coast and strait are also seeing light snowfall
amounts, especially the eastern strait with N/NE upslope flow
against the Olympics. Up north, strong Fraser outflow winds
continue with gusts of 40-60 mph across western WA county, leading
to bitter cold conditions and wind chills in the single digits.
Elsewhere, including Seattle and Everett, snow amounts will be
light and generally under an inch. Snow will linger in the south
sound/SW Interior Friday morning with chilly lows across the board
(temps in the 20s).

Another round of lowland snow is expected Friday night and
Saturday, with higher snowfall totals and wider coverage across
western WA. Pretty much all of western WA will see some snow but
there will be sharp gradients and ranges. Hood Canal south through
Olympia, Shelton and into Lewis county still show the highest
amounts based off the NBM guidance with an additional 8-10"
(possible up to 12") through Saturday afternoon. Most likely
scenario for the Seattle metro is 3-7" with highest amounts
toward Tacoma. Moving north toward Bellingham and San Juans,
there's less moisture but could still see 2-4". Overall,
significant impacts are possible based on these amounts. A big
limiting factor will be east winds and if they erode the moisture
layer, especially in the interior. Snow totals will still be
refined as we move toward the event but main messaging is to be
prepared for winter weather.

The air mass will moderate slightly on Sunday as Fraser outflow
winds ease and the flow turns more southerly. Highs will be near
40. We'll also see snow levels rising through the day although may
still see a rain/snow mix with additional accumulations generally
under an inch. 33

.LONG TERM /MONDAY THROUGH THURSDAY/...Moving into next week, a
modest warm up continues with snow levels rising to around
1000-2000 ft. So we're back to rain in the lowlands. Temperatures
will be above freezing and highs will be in the 40s. It's back to
an active pattern and impacts will likely be heavy mountain snow.
33

&&

.AVIATION...Northwesterly flow aloft will remain over W WA into Friday.
A weather system moving inland south of the area overnight will
continue to produce light snow at times from about KPAE southward with
best chance of accumulations over the southern third of Western
Washington. VFR ceilings expected across the far northern part of
Western Washington with MVFR and localized IFR conditions in light snow
across the southern half of Western Washington through Friday morning.
Strong low level offshore flow will continue to produce gusty east to
northeasterly surface winds reaching 30 to 40 knots at times near gaps
in terrain into Friday...including the Bellingham area, near the
Cascades, and portions of the coast.

KSEA...Overcast ceilings in the 030-040 range with occasional very
light snow. Little to no accumulation is expected as heavier activity
will remain to the south. Worst case scenario remains around an inch of
accumulation thru tonight but confidence in this scenario remains low.
Ceilings expected to deteriorate Friday night...with ceilings lowering
to MVFR with increasing snow and several inches of accumulation
expected. North to northeast wind generally 10-15 kt with gusts to 20
kt becoming more easterly overnight. 27/18

&&

.MARINE...High pressure to the north and east of Western Washington
with low pressure offshore is continuing the Fraser outflow over the
northern interior waters. Gale Warnings remain in effect for the
Northern Inland Waters, the Strait of Juan de Fuca, and the
Northern Coastal/Offshore Waters. SCAs cover the Central and
southern offshore/Coastal waters, Admiralty Inlet, and Puget
Sound, with some of these northerly winds becoming more easterly.

Winds will remain elevated through the overnight period and into
Friday. It currently appears that by Friday afternoon or evening the
Fraser outflow will subside and, in turn, the easterly winds will
really kick in as the pressure gradient strengthens. Model guidance
suggest a substantial surge of easterly wind down the Strait Friday
night-potentially approaching Storm criteria. Current solutions fall
just shy of that, but will have to monitor. Otherwise, could also
see another round of Gales offshore, with SCAs likely for the
remaining waters. Will leave these possibilities for next shift so
as to not create a log-jam when it comes to headlines.

Outside of the winds, winter precipitation should be expected, which
is likely to carry impacts. Moderate to heavy precip is likely over
Southern Puget Sound and the Southern Offshore/Coastal Waters today
and then across all waters Friday night into Saturday. Swells will
remain 5ft or less thru Friday, increasing quickly to 10-12 ft
Saturday and continuing into next week.

18/Carpenter

&&

.HYDROLOGY...No river flooding is expected over the next 7 days.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Storm Warning until 6 AM PST Friday for Hood Canal Area-
     Lower Chehalis Valley Area-Southwest Interior-Tacoma Area.

     Winter Storm Watch from 6 AM PST Friday through Saturday
     afternoon for Cascades of Pierce and Lewis Counties-Hood
     Canal Area-Lower Chehalis Valley Area-Southwest Interior-
     Tacoma Area.

     Wind Advisory until 10 AM PST Friday for Central Coast-North
     Coast-San Juan County-Western Whatcom County.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Admiralty Inlet Area-Bellevue and Vicinity-
     Bremerton and Vicinity-Central Coast-East Puget Sound
     Lowlands-Eastern Strait of Juan de Fuca-Everett and
     Vicinity-North Coast-Olympics-Seattle and Vicinity-Western
     Strait of Juan De Fuca.

     Winter Weather Advisory until 10 AM PST Friday for Central Coast-
     Eastern Strait of Juan de Fuca-North Coast-Western Strait
     of Juan De Fuca.

PZ...Small Craft Advisory until 11 AM PST Friday for Admiralty Inlet-
     Coastal Waters From James Island To Point Grenville 10 To
     60 Nm-Coastal Waters From James Island To Point Grenville
     Out 10 Nm-Coastal Waters From Point Grenville To Cape
     Shoalwater 10 To 60 Nm-Coastal Waters From Point Grenville
     To Cape Shoalwater Out 10 Nm.

     Gale Warning until 4 AM PST Saturday for Coastal Waters From
     Cape Flattery To James Island 10 To 60 Nm-Coastal Waters
     From Cape Flattery To James Island Out 10 Nm-West Entrance
     U.S. Waters Strait Of Juan De Fuca.

     Gale Watch from Friday evening through Saturday morning for
     Central U.S. Waters Strait Of Juan De Fuca-East Entrance
     U.S. Waters Strait Of Juan De Fuca.

     Gale Warning until 11 AM PST Friday for Central U.S. Waters
     Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of
     Juan De Fuca-Northern Inland Waters Including The San Juan
     Islands.

     Small Craft Advisory until midnight PST tonight for Puget Sound
     and Hood Canal.

&&

www.weather.gov/seattle

In the hours before

Local storm report, Feb 11, 6:08 PM PST, 5 hours 52 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SEATTLE WA
608 PM PST THU FEB 11 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0500 PM     HEAVY SNOW       7 E MCCLEARY            47.03N 123.11W
02/11/2021  M5.5 INCH        THURSTON           WA   PUBLIC

&&

Local storm report, Feb 11, 6:20 PM PST, 5 hours 40 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SEATTLE WA
620 PM PST THU FEB 11 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0600 PM     HEAVY SNOW       1.3 S OLYMPIA           47.02N 122.89W
02/11/2021  M4.7 INCH        THURSTON           WA   COCORAHS

&&

Local storm report, Feb 11, 9:50 PM PST, 2 hours 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SEATTLE WA
950 PM PST THU FEB 11 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0915 PM     HEAVY SNOW       1 E OLYMPIA             47.04N 122.87W
02/11/2021  M6.0 INCH        THURSTON           WA   PUBLIC

0915 PM     SNOW             4 NNW SEATTLE           47.67N 122.38W
02/11/2021  M0.4 INCH        KING               WA   PUBLIC

0900 PM     HEAVY SNOW       2 NE OLYMPIA            47.06N 122.85W
02/11/2021  M5.5 INCH        THURSTON           WA   PUBLIC

0900 PM     HEAVY SNOW       3 NW OLYMPIA            47.08N 122.94W
02/11/2021  M4.0 INCH        THURSTON           WA   PUBLIC

0900 PM     SNOW             2 WNW WHITE CENTER      47.54N 122.40W
02/11/2021  M1.0 INCH        KING               WA   PUBLIC

0835 PM     SNOW             3 SW SEATTLE            47.57N 122.39W
02/11/2021  M1.0 INCH        KING               WA   PUBLIC

&&

Local storm report, Feb 11, 10:04 PM PST, 1 hour 56 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SEATTLE WA
1004 PM PST THU FEB 11 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1003 PM     SNOW             CHEHALIS                46.66N 122.96W
02/11/2021  M5.0 INCH        LEWIS              WA   PUBLIC

            5 INCHES REPORTED JUST OUTSIDE OF CHEHALIS
            PER PUBLIC REPORT ON TWITTER.

&&

MK

Local storm report, Feb 11, 10:53 PM PST, 1 hour 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SEATTLE WA
1053 PM PST THU FEB 11 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1053 PM     SNOW             5 NNW DUPONT            47.16N 122.70W
02/11/2021  M1.5 INCH        PIERCE             WA   PUBLIC

            1.5 INCHES ANDERSON ISLAND VIA TWITTER
            REPORT.

&&

MK

Local storm report, Feb 11, 11:59 PM PST, 1 minute before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SEATTLE WA
1159 PM PST THU FEB 11 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1019 PM     SNOW             ASHFORD                 46.76N 122.03W
02/11/2021  M1.0 INCH        PIERCE             WA   PUBLIC

1100 PM     SNOW             BOTHELL                 47.76N 122.21W
02/11/2021  M0.5 INCH        KING               WA   PUBLIC

0953 PM     SNOW             4.6 NE SEATTLE          47.65N 122.26W
02/11/2021  M0.5 INCH        KING               WA   PUBLIC

&&

Event by event

1 ice storm. Local standard time, as filed.

Ice Storm, Central Coast

When: February 12, 12:00 AM PST to February 13, 7:00 AM PST
Where: Central Coast forecast zone
Reported by: Public

During the overnight hours on February 12th, reports from the public began to come in regarding significant (at least 1/4) ice accumulation on many surfaces. Areas from around Ocean Shores to Pacific reportedly received the highest amounts of ice accumulation. Precipitation would then move more inland/to the east during the later morning hours, ending the highest chances for ice.

What these are

Ice Storm: Freezing rain accumulating a quarter inch or more of ice, or less where it caused significant damage.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Washington in 2021 Every state in 2021 This day in weather history Warnings in Washington, February 2021

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 945359.