Winter Weather in Wisconsin, February 13, 2021

Name: Winter Weather in Wisconsin, February 13, 2021
Start: 2021-02-13T02:15
End: 2021-02-13T16:15
Location: Wisconsin

February 13, 2021 · NWS MKX · 20 events in 20 counties and zones

An upper level disturbance brought light, powdery snow to southern WI during very cold conditions. The small amount of snow created very slippery road conditions, resulting in numerous vehicle slide-offs and accidents on Interstates and in urban areas.

Where it happened

Every event with a place to put it; 20 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 20

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 MKX 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 Milwaukee, WI wrote its last area forecast discussion before the first event at Feb 12, 9:21 PM CST, 4 hours 54 minutes earlier.

Area forecast discussion, Feb 12, 9:21 PM CST, 4 hours 54 minutes before

Area Forecast Discussion...UPDATED
National Weather Service Milwaukee/Sullivan WI
921 PM CST Fri Feb 12 2021

.UPDATE...
(Issued 921 PM CST Fri Feb 12 2021)

Wind Chill Advisory for the western half of the area until Noon
CST Saturday still looks good. The next tier of counties to the
east may be close to the 20 below zero threshold toward 12z
Saturday, but will let night shift take a look at the full suite
of models before adding any additional counties.

Light snow is developing over parts of northern Illinois into
east central Iowa, where low level frontogenesis, some
differential CVA within 500 mb flow and upper divergence is
occurring. More light snow is occurring to the west over central
and western Iowa, associated with differential CVA from the main
500 mb vorticity maximum.

This area of light snow should continue to gradually push east
northeast into the area overnight into Saturday morning, along
with the low level frontogenesis response pushing northward from
northern Illinois. It may take a little more time for the air
column to saturate than currently forecast, but will wait for
suite of 00z deterministic models to come in before adjusting
timing.

Forecast soundings show a rather deep dendrite snow growth zone
overnight into Saturday morning, mainly in the southeast half of
the area. Snow to liquid ratios should be in the upper teens to
around 20 to 1 in these areas. Less potential for a deep dendrite
zone to the northwest, where snow to liquid ratios may end up
lower. These will be key for snow accumulations.

Ensembles are showing perhaps an inch across the area, with
PWPF/WPC QPF 25th/75th percentiles and deterministic models
showing a 1 to 2 inch snowfall, highest in eastern parts of the
area. Not much in the way of lake enhancement is expected, as low
level flow remains largely offshore.

For now, still expecting fluffy, powdery snow to occur later
tonight into Saturday morning, with snow covered and slippery
roads developing. Will maintain current messaging for now.

Wood

&&

.SHORT TERM...
(Issued 258 PM CST Fri Feb 12 2021)

Tonight through Monday night:

A shortwave trough currently over srn British Columbia, Canada
will dive sewd into the central Great Plains late tnt then swing
enewd across srn WI for Sat aft. As the mid to upper level flow
turns swly ahead of this feature, the mid level baroclinic zone
currently from srn IA to nrn IL will become more active via WAA
and mid level frontogenesis and shift nwd into srn WI. Thus light
snow will gradually overspread srn WI from south to north between
midnight and 5 am. The shortwave trough and associated PVA
combined with sfc-850 mb frontogenesis will keep the light snow
going for much of Sat. Overall, the lift will be fairly weak
but still expecting 1-2 inches of snow with greater values over
ern WI. There may be a brief period of lake enhancement but
overall looks minimal.

For tnt, a Wind Chill Advisory is in effect over south central
WI. Greater cold advection is expected Sat nt after the shortwave
trough passage. A frigid airmass will invade the area with more
Wind Chill Advisories needed for night and mornings through Monday
morning. It's unlikely at this time Wind Chill Warnings would be
needed. Will also have small chances for light snow mainly over se
WI from Sun nt-Mon nt due to a shortwave trough going through the
Ohio River Valley.

Gehring

&&

.LONG TERM...
(Issued 258 PM CST Fri Feb 12 2021)

Tuesday through Friday:

The large upper low that has been over southern Canada will
finally get kicked ewd by this period and it will take some of the
arctic air with it.

The srn stream jet stream will be fairly active just south of the
region. It is possible to get clipped by light snow or even have
light LES during this time. High temps may actually reach the 20s
for Wed and beyond.

Gehring

&&

.AVIATION...
(Issued 921 PM CST Fri Feb 12 2021)

Snow should spread east northeast into the area between 08z and
12z Saturday, lingering until around 21z Saturday to 00z Sunday
before exiting. Worst conditions should be 12z to 20z Saturday,
with around 1 mile visibility and ceilings around 1000 to 1500
feet AGL. Brief lower visibility and ceilings may occur at times.
This will be a fluffy, powdery snow.

Winds should be northwest and light during most of the period of
snow, with northwest gusts of 15 to 18 knots developing later in
the afternoon and into Saturday night. Skies should clear out
Saturday night from west to east, with VFR conditions returning.

Wood

&&

.MARINE...
(Issued 258 PM CST Fri Feb 12 2021)

Strong high pressure will remain over the northern Great Plains
and the Upper MS River Valley into early next week. This will
continue to bring modest to brisk nly winds. Light to moderate
freezing spray is expected given the very cold air and some wave
action.

Gehring

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Wind Chill Advisory...WIZ046-WIZ047-WIZ056-WIZ057-WIZ062-WIZ063-
     WIZ067-WIZ068 until noon Saturday.

LM...None.
&&

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Hazardous weather outlook, Feb 12, 9:24 PM CST, 4 hours 51 minutes before

Hazardous Weather Outlook...UPDATED
National Weather Service Milwaukee/Sullivan WI
924 PM CST Fri Feb 12 2021

WIZ046-047-051-052-056>060-062>072-140330-
Marquette-Green Lake-Fond du Lac-Sheboygan-Sauk-Columbia-Dodge-
Washington-Ozaukee-Iowa-Dane-Jefferson-Waukesha-Milwaukee-
Lafayette-Green-Rock-Walworth-Racine-Kenosha-
924 PM CST Fri Feb 12 2021

This Hazardous Weather Outlook is for portions of east central
Wisconsin, south central Wisconsin and southeast Wisconsin.

.DAY ONE...Rest Of Tonight

Another round of light accumulating snow will move east
northeastward into the area overnight, resulting in snow covered
and slippery roads once again.

A Wind Chill Advisory is in effect across south central Wisconsin
for wind chills of 15 to 25 below zero.

.DAYS TWO THROUGH SEVEN...Saturday through Friday

The light snow will continue for much of Saturday, with totals of
1 to 3 inches forecast, highest in eastern parts of the area.

The Wind Chill Advisory remains in effect until noon on Saturday
over south central Wisconsin.

Very cold temperatures and frigid wind chills are expected to
continue into early next week, with the likelihood for more Wind
Chill Advisories from Saturday night into Monday morning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed, but snowfall reports are
appreciated.

LMZ643>646-140330-
Sheboygan to Port Washington WI-
Port Washington to North Point Light WI-
North Point Light to Wind Point WI-
Wind Point WI to Winthrop Harbor IL-
924 PM CST Fri Feb 12 2021

This Hazardous Weather Outlook is for the nearshore waters from
Sheboygan Wisconsin to Winthrop Harbor Illinois.

.DAY ONE...Rest Of Tonight

No Hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Friday

North to northwest winds may approach Small Craft Advisory levels
over the weekend.

Freezing spray will be possible at times through the weekend.

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-140330-
Lake Michigan Michigan City IN to St. Joseph MI 5 NM offshore to
mid-line of lake.-
Lake Michigan from Seul Choix Point to Rock Island Passage 5NM
offshore to Mid Lake-
Lake Michigan South of a line from Seul Choix Point to the
Mackinac Bridge and North of a line from Charlevoix MI to South
Fox Island 5NM offshore-
Lake Michigan from Charlevoix to Point Betsie MI 5NM Offshore to
mid lake-
Lake Michigan from Point Betsie to Manistee MI 5NM offshore to
Mid Lake-
Lake Michigan from Rock Island Passage to Sturgeon Bay WI 5NM
offshore to mid lake-
Lake Michigan from Sturgeon Bay to Two Rivers WI 5NM offshore to
Mid Lake-
Lake Michigan from Two Rivers to Sheboygan WI 5NM offshore to Mid
Lake-
Lake Michigan from Sheboygan to Port Washington WI 5NM offshore
to Mid Lake-
Lake Michigan from Port Washington to North Point Light WI 5NM
offshore to Mid Lake-
Lake Michigan from North Point Light to Wind Point WI 5NM
offshore to Mid Lake-
Lake Michigan from Wind Point WI to Winthrop Harbor IL 5NM
offshore to Mid Lake-
Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5NM
offshore to Mid Lake-
Lake Michigan from Wilmette Harbor to Michigan City in 5NM
offshore to Mid Lake-
Lake Michigan from Pentwater to Manistee MI 5NM offshore to Mid
Lake-
Lake Michigan from Whitehall to Pentwater MI 5NM offshore to Mid
Lake-
Lake Michigan from Grand Haven to Whitehall MI 5NM offshore to
Mid Lake-
Lake Michigan from Holland to Grand Haven MI 5NM offshore to Mid
Lake-
Lake Michigan from South Haven to Holland MI 5NM offshore to Mid
lake-
Lake Michigan from St Joseph to South Haven MI 5NM offshore to
Mid Lake-
924 PM CST Fri Feb 12 2021

This Hazardous Weather Outlook is for the open waters of Lake Michigan.

.DAY ONE...Rest Of Tonight

Freezing spray is possible, especially across the southern half
of the lake.

.DAYS TWO THROUGH SEVEN...Saturday through Friday

Freezing spray will be possible at times through the weekend.

Wood
www.weather.gov/mkx

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

20 winter weather. Local standard time, as filed.

Winter Weather, Lafayette

When: February 13, 2:15 AM CST to 1:30 PM CST
Where: Lafayette forecast zone
Reported by: Trained Spotter
Coordinates: 42.661, -90.132 (the zone’s center; the record gives no point)

Snow accumulation 1-2 inches.

Winter Weather, Green

When: February 13, 3:00 AM CST to 2:15 PM CST
Where: Green forecast zone
Reported by: Trained Spotter
Coordinates: 42.680, -89.602 (the zone’s center; the record gives no point)

Snow accumulation of 1-2 inches.

Winter Weather, Iowa

When: February 13, 3:00 AM CST to 1:30 PM CST
Where: Iowa forecast zone
Reported by: Trained Spotter
Coordinates: 43.001, -90.135 (the zone’s center; the record gives no point)

Snow accumulation around 1 inch.

Winter Weather, Dane

When: February 13, 3:30 AM CST to 2:45 PM CST
Where: Dane forecast zone
Reported by: Trained Spotter
Coordinates: 43.067, -89.418 (the zone’s center; the record gives no point)

Snow accumulation of 1-2 inches.

Winter Weather, Kenosha

When: February 13, 3:30 AM CST to 4:15 PM CST
Where: Kenosha forecast zone
Reported by: Trained Spotter
Coordinates: 42.573, -87.840 (the zone’s center; the record gives no point)

Snow accumulation 1-2 inches.

Winter Weather, Rock

When: February 13, 3:30 AM CST to 3:15 PM CST
Where: Rock forecast zone
Reported by: Trained Spotter
Coordinates: 42.671, -89.072 (the zone’s center; the record gives no point)

Snow accumulation 1-2 inches.

Winter Weather, Walworth

When: February 13, 3:30 AM CST to 3:45 PM CST
Where: Walworth forecast zone
Reported by: Trained Spotter
Coordinates: 42.669, -88.542 (the zone’s center; the record gives no point)

Snow accumulation 1-2 inches.

Winter Weather, Sauk

When: February 13, 3:30 AM CST to 1:30 PM CST
Where: Sauk forecast zone
Reported by: Trained Spotter
Coordinates: 43.427, -89.948 (the zone’s center; the record gives no point)

Snow accumulation around 1 inch.

Winter Weather, Columbia

When: February 13, 3:45 AM CST to 2:45 PM CST
Where: Columbia forecast zone
Reported by: Trained Spotter
Coordinates: 43.467, -89.334 (the zone’s center; the record gives no point)

Snow accumulation of 1-2 inches.

Winter Weather, Dodge

When: February 13, 4:00 AM CST to 3:30 PM CST
Where: Dodge forecast zone
Reported by: Trained Spotter
Coordinates: 43.416, -88.707 (the zone’s center; the record gives no point)

Snow accumulation of 1-2 inches.

Winter Weather, Green Lake

When: February 13, 4:00 AM CST to 2:15 PM CST
Where: Green Lake forecast zone
Reported by: Trained Spotter
Coordinates: 43.800, -89.045 (the zone’s center; the record gives no point)

Snow accumulation around 1 inch.

Winter Weather, Marquette

When: February 13, 4:00 AM CST to 2:00 PM CST
Where: Marquette forecast zone
Reported by: Trained Spotter
Coordinates: 43.820, -89.399 (the zone’s center; the record gives no point)

Snow accumulation around 1 inch.

Winter Weather, Jefferson

When: February 13, 4:00 AM CST to 3:30 PM CST
Where: Jefferson forecast zone
Reported by: Trained Spotter
Coordinates: 43.021, -88.776 (the zone’s center; the record gives no point)

Snow accumulation 1-2 inches.

Winter Weather, Sheboygan

When: February 13, 4:00 AM CST to 3:15 PM CST
Where: Sheboygan forecast zone
Reported by: Trained Spotter
Coordinates: 43.756, -87.800 (the zone’s center; the record gives no point)

Snow accumulation 1-2 inches.

Winter Weather, Ozaukee

When: February 13, 4:15 AM CST to 3:45 PM CST
Where: Ozaukee forecast zone
Reported by: Trained Spotter
Coordinates: 43.403, -87.891 (the zone’s center; the record gives no point)

Snow accumulation 1-3 inches.

Winter Weather, Washington

When: February 13, 4:15 AM CST to 3:45 PM CST
Where: Washington forecast zone
Reported by: Trained Spotter
Coordinates: 43.369, -88.231 (the zone’s center; the record gives no point)

Snow accumulation 1-2 inches.

Winter Weather, Fond du Lac

When: February 13, 4:30 AM CST to 3:00 PM CST
Where: Fond du Lac forecast zone
Reported by: Trained Spotter
Coordinates: 43.754, -88.488 (the zone’s center; the record gives no point)

Snow accumulation of 1-2 inches.

Winter Weather, Racine

When: February 13, 4:45 AM CST to 4:15 PM CST
Where: Racine forecast zone
Reported by: Trained Spotter
Coordinates: 42.730, -87.812 (the zone’s center; the record gives no point)

Snow accumulation 1-3 inches.

Winter Weather, Milwaukee

When: February 13, 4:45 AM CST to 4:15 PM CST
Where: Milwaukee forecast zone
Reported by: Trained Spotter
Coordinates: 43.022, -87.929 (the zone’s center; the record gives no point)

Snow accumulation 2-4 inches.

Winter Weather, Waukesha

When: February 13, 4:45 AM CST to 4:00 PM CST
Where: Waukesha forecast zone
Reported by: Trained Spotter
Coordinates: 43.018, -88.304 (the zone’s center; the record gives no point)

Snow accumulation 1-2 inches.

What these are

Winter Weather: Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.

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

The same day elsewhere

Every storm in Wisconsin in 2021 Every state in 2021 This day in weather history Warnings in Wisconsin, 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: 936914, 936907, 936910, 936904, 936912, 936913, 936919, 936922, 936903, 936905, 936908, 936909, 936911, 936918, 936917, 936921, 936906, 936915, 936916, 936920.