Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 36, NWS Twin Cities, MN

April 17, 2026Pierce County, Saint Croix County, Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at Apr 17, 2026, 2:06 PM CDT for Pierce County, Saint Croix County, Wisconsin. It was in force for 33 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Apr 17, 2026, 2:06 PM CDT (19:06 UTC)
Expired
Apr 17, 2026, 2:39 PM CDT
In force
33 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.25 in
Wind
50.0 mph

Counties Pierce County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 92 km from the middle of the area, began a volume at 19:08 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Apr 17, 2:14 PM CDTHAIL 12 E Ellsworth, WI
Apr 17, 2:47 PM CDTHAIL 1.254 Nnw Bay City, WIEmailed photos of large hail in backyard. Time estimated via radar.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 3 storm reports to this severe thunderstorm warning; the first came 2 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 17, 9:23 AM CDTSevere Thunderstorm WatchSPC11 hr
Apr 17, 12:40 PM CDTTornado WatchSPC9 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 7.1 hours before the alert went out and 94 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2026-04-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2026-04-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 188 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2301 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
188 m²/s²
0-3 km storm-relative helicity
229 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

932 
WUUS53 KMPX 171906
SVRMPX
WIC093-109-171945-
/O.NEW.KMPX.SV.W.0036.260417T1906Z-260417T1945Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
206 PM CDT Fri Apr 17 2026

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Eastern Pierce County in west central Wisconsin...
  Southeastern St. Croix County in west central Wisconsin...

* Until 245 PM CDT.

* At 206 PM CDT, a severe thunderstorm was located over Bay City, or
  over Red Wing, moving northeast at 60 mph.

  HAZARD...Half dollar size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Red Wing Airport, Hager City, Bay City, Esdaile, Ellsworth, El
  Paso, Martel, Baldwin, Woodville, Wilson and Hersey.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. This storm is capable of producing large hail.

A Tornado Watch remains in effect until 800 PM CDT Friday for a
portion of west central Wisconsin.

&&

LAT...LON 4461 9260 4500 9234 4496 9214 4482 9214
      4455 9232 4456 9236 4456 9240 4457 9243
      4456 9246 4457 9248 4457 9249 4458 9252
      4457 9255 4458 9255 4460 9257 4460 9259
TIME...MOT...LOC 1906Z 210DEG 51KT 4457 9250

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

BED
3 follow-up statements
654 
WWUS53 KMPX 171918
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
218 PM CDT Fri Apr 17 2026

WIC093-109-171945-
/O.CON.KMPX.SV.W.0036.000000T0000Z-260417T1945Z/
Pierce WI-St. Croix WI-
218 PM CDT Fri Apr 17 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 245 PM CDT FOR
NORTHEASTERN PIERCE AND SOUTHEASTERN ST. CROIX COUNTIES...

At 218 PM CDT, a severe thunderstorm was located 7 miles east of
Ellsworth, or 15 miles southeast of River Falls, moving northeast at
55 mph.

HAZARD...Half dollar size hail.

SOURCE...Trained spotters reported. At 2:15PM a trained spotter
         reported 1.00 inch size hail 2 miles east of Ellsworth.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
  Ellsworth, El Paso, Martel, Woodville, Hersey and Wilson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. This storm has produced large hail.

A Tornado Watch remains in effect until 800 PM CDT Friday for a
portion of west central Wisconsin.

&&

LAT...LON 4486 9243 4500 9234 4496 9214 4482 9214
      4474 9220 4462 9228 4463 9245 4470 9254
TIME...MOT...LOC 1906Z 219DEG 48KT 4464 9249

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

BED
309 
WWUS53 KMPX 171928
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
228 PM CDT Fri Apr 17 2026

WIC093-109-171945-
/O.CON.KMPX.SV.W.0036.000000T0000Z-260417T1945Z/
Pierce WI-St. Croix WI-
228 PM CDT Fri Apr 17 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 245 PM CDT FOR
NORTHEASTERN PIERCE AND SOUTHEASTERN ST. CROIX COUNTIES...

At 228 PM CDT, a severe thunderstorm was located 6 miles south of
Woodville, or 16 miles east of River Falls, moving northeast at 50
mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
  El Paso, Martel, Woodville, Hersey and Wilson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. This storm is capable of producing large hail.

A Tornado Watch remains in effect until 800 PM CDT Friday for a
portion of west central Wisconsin.

&&

LAT...LON 4486 9243 4500 9234 4496 9214 4486 9214
      4480 9219 4475 9230 4479 9248
TIME...MOT...LOC 1918Z 211DEG 41KT 4477 9238

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

BED
877 
WWUS53 KMPX 171939
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
239 PM CDT Fri Apr 17 2026

WIC093-109-171949-
/O.CAN.KMPX.SV.W.0036.000000T0000Z-260417T1945Z/
Pierce WI-St. Croix WI-
239 PM CDT Fri Apr 17 2026

...SEVERE THUNDERSTORM WARNING IS CANCELLED FOR NORTHEASTERN PIERCE
AND SOUTHEASTERN ST. CROIX COUNTIES...

The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has
been cancelled.

A Tornado Watch remains in effect until 800 PM CDT Friday for a
portion of west central Wisconsin.

A Severe Thunderstorm Watch remains in effect until 500 PM CDT for a
portion of west central Wisconsin.

&&

LAT...LON 4486 9243 4500 9234 4496 9214 4486 9214
      4480 9219 4475 9230 4479 9248
TIME...MOT...LOC 1928Z 211DEG 41KT 4487 9229

$$

BED

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Twin Cities, MN wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 17, 2:02 PM CDT, 4 minutes earlier. Its key messages:

  • The passage of a strong cold front today will bring scattered thunderstorms. As of 1pm, the severe weather risk is mainly across western Wisconsin.
  • Large hail and damaging winds are the primary hazards across western Wisconsin, and the risk for tornadoes increases as you head east.
  • Much colder air is expected for the weekend with possibly a few snow showers but with no snow accumulation.
Area forecast discussion, Apr 17, 2:02 PM CDT, 4 minutes before
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
202 PM CDT Fri Apr 17 2026

.KEY MESSAGES...

- The passage of a strong cold front today will bring scattered
  thunderstorms. As of 1pm, the severe weather risk is mainly
  across western Wisconsin.

- Large hail and damaging winds are the primary hazards across
  western Wisconsin, and the risk for tornadoes increases as you
  head east.

- Much colder air is expected for the weekend with possibly a
  few snow showers but with no snow accumulation.

&&

.DISCUSSION...
Issued at 1257 PM CDT Fri Apr 17 2026

Today:
Early afternoon satellite and radar imagery
showed storms across central and western Minnesota. These storms
were behind a strong cold front that as of 1pm were generally
along the I-35 corridor. At Jackson Minnesota, the temperature
dropped 22 degrees in 41 minutes earlier today!

Meanwhile, a few storms were developing ahead of the cold
front, and these are the ones that could produce large hail,
damaging wind, and tornadoes later this afternoon. For this
afternoon, severe thunderstorm watches and tornado watches have
been issued for a few counties in far eastern MN, and much of
Wisconsin.

There is strong forcing for severe weather, meaning the CAP will
not hold. However, we expect storms to quickly develop which
could lead to destructive interference. But the overall
environment does support strong to severe storms through
roughly 3 to 5 pm in our area, and then we expect the convection
to be east of Rusk, Chippewa, and Eau Claire counties. As for
the rain threat, these storms will be moving quickly, so most
locations will have less than an inch.

Tonight through Thursday:

Once the storms exit the region, northwest winds will continue
to bring in cold air overnight, with lows falling below freezing
across the region. The cold air will continue though Saturday,
with highs only in the mid 40s, and breezy northwest winds
continuing, keeping wind chills near freezing throughout the
day.

On Sunday, high pressure will build in and temperatures will be
a bit warmer, with highs in the upper 40s. The real warmth
returns on Monday, with highs back in the 60s. This is in
response to upper level ridging building across the central
CONUS, and warm air advection overspreading across the region.

This ridge will also keep the region dry through Wednesday. On
Thursday troughing from the west will bring increased moisture
across the region, and high chances (50 to 70) for showers and
thunderstorms.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1257 PM CDT Fri Apr 17 2026

Main concern in the short term is showers and thunderstorms this
afternoon, but they should diminish from west to east during the
late afternoon and into the evening as a cold front continue to
move through the region. This will bring northwest winds and
MVFR ceilings. Ceilings will start raise, and expect mostly VFR
conditions on Saturday.

KMSP...
Expect scattered showers and thunderstorms this afternoon with
northwest winds and MVFR ceilings. Then ceilings will lift and
expect VFR conditions after that.

/OUTLOOK FOR KMSP/
SUN...VFR. Wind NW 5-10kts.
MON...VFR. Wind SE 10kts becoming S 10G20kts.
TUE...VFR. Wind SW 5-10kts becoming NW.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.

&&

DISCUSSION...JRB
AVIATION...JRB
Hazardous weather outlook, Apr 17, 4:13 AM CDT, 9 hours 53 minutes before
Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
413 AM CDT Fri Apr 17 2026

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
180900-
Douglas-Todd-Morrison-Mille Lacs-Kanabec-Stevens-Pope-Stearns-
Benton-Sherburne-Isanti-Chisago-Lac Qui Parle-Swift-Chippewa-
Kandiyohi-Meeker-Wright-Hennepin-Anoka-Ramsey-Washington-
Yellow Medicine-Renville-McLeod-Sibley-Carver-Scott-Dakota-
Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-Blue Earth-
Waseca-Steele-Martin-Faribault-Freeborn-Polk-Barron-Rusk-
St. Croix-Pierce-Dunn-Pepin-Eau Claire-
413 AM CDT Fri Apr 17 2026

This Hazardous Weather Outlook is for portions of central and
southern Minnesota, and west central Wisconsin.

.DAY ONE...Today and Tonight.

A strong cold front will push across the area today. A line of
strong to severe thunderstorms will develop along it across
eastern Minnesota late this morning into early this afternoon,
then track quickly across western Wisconsin. Large hail, damaging
winds, and a tornado or two are possible, especially in Wisconsin.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation may be needed this afternoon, mainly in
eastern Minnesota into western WI.

In the hours before

Local storm report, Apr 17, 9:38 AM CDT, 4 hours 28 minutes before
Preliminary Local Storm Report
National Weather Service Twin Cities/Chanhassen MN
938 AM CDT Fri Apr 17 2026

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

0930 AM     Hail             4 NE Faribault          44.33N 93.21W
04/17/2026  M1.00 Inch       Rice               MN   Trained Spotter

&&
Local storm report, Apr 17, 10:15 AM CDT, 3 hours 51 minutes before
Preliminary Local Storm Report
National Weather Service Twin Cities/Chanhassen MN
1015 AM CDT Fri Apr 17 2026

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

1008 AM     Hail             1 S Cannon Falls        44.49N 92.91W
04/17/2026  M1.00 Inch       Goodhue            MN   Public

&&
Local storm report, Apr 17, 10:39 AM CDT, 3 hours 27 minutes before
Preliminary Local Storm Report
National Weather Service Twin Cities/Chanhassen MN
1039 AM CDT Fri Apr 17 2026

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

1012 AM     Hail             2 SSW Cannon Falls      44.48N 92.92W
04/17/2026  M1.00 Inch       Goodhue            MN   Trained Spotter

            Hail measurement photo provided via NWSChat.
            Time estimated via radar.

&&

RMD
Special weather statement, Apr 17, 10:57 AM CDT, 3 hours 9 minutes before
Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
1057 AM CDT Fri Apr 17 2026

WIZ023-024-171645-
Pierce WI-St. Croix WI-
1057 AM CDT Fri Apr 17 2026

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL ST. CROIX AND NORTH
CENTRAL PIERCE COUNTIES UNTIL 1145 AM CDT...

At 1057 AM CDT, Doppler radar was tracking a strong thunderstorm over
River Falls, moving northeast at 30 mph.

HAZARD...Wind gusts up to 40 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
  River Falls, Hammond, Baldwin, Roberts, Woodville, Glenwood City,
  Emerald, Cylon, Deer Park, Martel, Hersey and Beldenville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the weather situation closely and be alert for threatening
weather conditions.

&&

LAT...LON 4485 9272 4520 9238 4506 9214 4501 9214
      4474 9252
TIME...MOT...LOC 1557Z 218DEG 27KT 4483 9257

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...40 MPH

MPG
Local storm report, Apr 17, 11:22 AM CDT, 2 hours 44 minutes before
Preliminary Local Storm Report
National Weather Service Twin Cities/Chanhassen MN
1122 AM CDT Fri Apr 17 2026

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

1000 AM     Hail             Hastings                44.74N 92.85W
04/17/2026  M0.88 Inch       Dakota             MN   Public

            Measurement provided via Facebook. Time
            estimated via radar.

&&

RMD
Special weather statement, Apr 17, 1:53 PM CDT, 13 minutes before
Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
153 PM CDT Fri Apr 17 2026

MNZ060-062-069-171930-
Ramsey MN-Scott MN-Hennepin MN-
153 PM CDT Fri Apr 17 2026

...A STRONG THUNDERSTORM WILL IMPACT HENNEPIN...SOUTHWESTERN RAMSEY
AND NORTHEASTERN SCOTT COUNTIES UNTIL 230 PM CDT...

At 153 PM CDT, Doppler radar was tracking a strong thunderstorm over
Eden Prairie, or 13 miles southwest of Minneapolis, moving northeast
at 55 mph.

HAZARD...Nickel size hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to outdoor objects is possible.

Locations impacted include...
  Minneapolis, St. Paul, Bloomington, Brooklyn Park, Eden Prairie,
  Minnetonka, Edina, St. Louis Park, Shakopee, Richfield, Roseville,
  Brooklyn Center, Savage, Prior Lake and New Brighton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the weather situation closely and be alert for threatening
weather conditions.

&&

LAT...LON 4488 9352 4511 9333 4509 9328 4504 9328
      4504 9323 4506 9323 4499 9306 4481 9326
      4479 9333 4475 9333 4472 9336 4480 9354
      4480 9352
TIME...MOT...LOC 1852Z 214DEG 45KT 4482 9342

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...<30 MPH

Dunleavy

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 17, 10:10 AM CDTSevere Thunderstorm WarningMPXPierce50 min
Apr 17, 10:57 AM CDTSpecial Weather StatementMPXSaint Croix48 min
Apr 17, 2:27 PM CDTSpecial Weather StatementMPXBarron, Chippewa, Dunn, Polk, Rusk, Saint Croix93 min
Apr 17, 2:34 PM CDTSevere Thunderstorm WarningMPXBarron, Polk41 min
Apr 17, 2:35 PM CDTSevere Thunderstorm WarningMPXChippewa10 min
Apr 17, 2:42 PM CDTSevere Thunderstorm WarningMPXPierce33 min
Apr 17, 3:08 PM CDTSevere Thunderstorm WarningMPXBarron, Dunn, Polk, Saint Croix35 min
Apr 17, 3:09 PM CDTSevere Thunderstorm WarningMPXBarron36 min
Apr 17, 3:17 PM CDTSevere Thunderstorm WarningMPXDunn26 min
Apr 17, 4:13 PM CDTTornado WarningMPXEau Claire32 min

Nearby

Severe Thunderstorm Warnings in Wisconsin, 2026Every severe thunderstorm warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.