Alert archive / Wisconsin / Tornado Warnings in 2021

Tornado Warning 11, NWS Green Bay, WI

August 11, 2021Marathon County, Wisconsin

NWS Green Bay, WI issued this tornado warning at Aug 11, 2021, 2:09 PM CDT for Marathon County, Wisconsin. It was in force for 51 min. 1 report 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
Aug 11, 2021, 2:09 PM CDT (19:09 UTC)
Expired
Aug 11, 2021, 3:00 PM CDT
In force
51 min
Issued by
NWS Green Bay, WI
Area
Storm-based polygon
Tornado
Observed
Hail
0.75 in

County Marathon County, WI

The radar

The La Crosse radar (KARX), 142 km from the middle of the area, began a volume at 19:09 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
Aug 11, 2:55 PM CDTTSTM WND GST 46Mosinee, WI

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

The watch it was issued in

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

IssuedProductOfficeLasted
Aug 11, 12:17 PM CDTTornado WatchSPC8 hr

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 7.2 hours before the alert went out and 152 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, Green Bay/Straub, WI at 12:00Z on 2021-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1499 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Green Bay/Straub, WI at 12:00Z on 2021-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 156 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
1499 J/kg
Mixed-layer CIN
-136 J/kg
Mixed-layer LCL
678 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
156 m²/s²
0-3 km storm-relative helicity
206 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

As transmitted.

250 
WFUS53 KGRB 111909
TORGRB
WIC073-112000-
/O.NEW.KGRB.TO.W.0011.210811T1909Z-210811T2000Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Green Bay WI
209 PM CDT Wed Aug 11 2021

The National Weather Service in Green Bay has issued a

* Tornado Warning for...
  Southwestern Marathon County in central Wisconsin...

* Until 300 PM CDT.

* At 209 PM CDT, a confirmed tornado was located near Marshfield, or
  26 miles northeast of Neillsville, moving east at 35 mph.

  HAZARD...Damaging tornado.

  SOURCE...Law enforcement confirmed tornado.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* The tornado will be near...
  Mosinee around 245 PM CDT.

Other locations impacted by this tornadic thunderstorm include
Rozellville, Big Eau Pleine County Park, Moon, Halder, Stratford,
Knowlton, Evergreen, Peplin and Rothschild.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. TAKE COVER NOW! Move to a
basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

&&

LAT...LON 4469 9022 4482 9023 4489 8963 4469 8961
TIME...MOT...LOC 1909Z 267DEG 31KT 4474 9012 

TORNADO...OBSERVED
MAX HAIL SIZE...<.75 IN

$$

Kieckbusch
3 follow-up statements
546 
WWUS53 KGRB 111916
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
216 PM CDT Wed Aug 11 2021

WIC073-112000-
/O.CON.KGRB.TO.W.0011.000000T0000Z-210811T2000Z/
Marathon WI-
216 PM CDT Wed Aug 11 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 300 PM CDT FOR
SOUTHWESTERN MARATHON COUNTY...
    
At 216 PM CDT, a severe thunderstorm capable of producing a tornado
was located 8 miles northeast of Marshfield, or 24 miles southwest of
Wausau, moving east at 35 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Mosinee around 245 PM CDT.

Other locations impacted by this tornadic thunderstorm include
Rozellville, Big Eau Pleine County Park, Moon, Halder, Stratford,
Knowlton, Evergreen, Peplin and Rothschild.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4469 9015 4482 9018 4489 8963 4469 8961
TIME...MOT...LOC 1916Z 267DEG 31KT 4474 9003 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Kieckbusch
292 
WWUS53 KGRB 111931
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
231 PM CDT Wed Aug 11 2021

WIC073-112000-
/O.CON.KGRB.TO.W.0011.000000T0000Z-210811T2000Z/
Marathon WI-
231 PM CDT Wed Aug 11 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 300 PM CDT FOR SOUTH
CENTRAL MARATHON COUNTY...
    
At 231 PM CDT, a confirmed tornado was located near Mosinee, or 15
miles south of Wausau, moving east at 50 mph.

HAZARD...Damaging tornado.

SOURCE...Law enforcement confirmed tornado.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornado will be near...
  Mosinee around 235 PM CDT.

Other locations impacted by this tornadic thunderstorm include
Rozellville, Big Eau Pleine County Park, Moon, Halder, Knowlton,
Evergreen, Peplin, Stratford and Rothschild.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. TAKE COVER NOW! Move to a
basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4470 9005 4482 9007 4489 8963 4469 8961
TIME...MOT...LOC 1931Z 267DEG 46KT 4475 8976 

TORNADO...OBSERVED
MAX HAIL SIZE...<.75 IN

$$

Kieckbusch
964 
WWUS53 KGRB 111939
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
239 PM CDT Wed Aug 11 2021

WIC073-112000-
/O.CON.KGRB.TO.W.0011.000000T0000Z-210811T2000Z/
Marathon WI-
239 PM CDT Wed Aug 11 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 300 PM CDT FOR SOUTH
CENTRAL MARATHON COUNTY...
    
At 238 PM CDT, a severe thunderstorm capable of producing a tornado 
was located 2 miles east of Mosinee, or 15 miles south of Wausau, 
moving east at 35 mph. Another possible area of rotation was located 
southwest of Halder.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
south central Marathon County, including the following locations...
Halder, Big Eau Pleine County Park, Knowlton, Moon, Evergreen and
Rothschild.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4470 8997 4479 9003 4486 8963 4469 8961
TIME...MOT...LOC 1938Z 269DEG 32KT 4474 8968 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Kieckbusch

The office that day

Everything else NWS Green Bay, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 10, 7:00 PM CDTSpecial Marine WarningGRB60 min
Aug 10, 7:06 PM CDTSpecial Marine WarningGRB54 min
Aug 10, 7:11 PM CDTFlash Flood WarningGRBBrown3 hr
Aug 10, 7:20 PM CDTSpecial Weather StatementGRBCalumet, Manitowoc55 min
Aug 10, 7:30 PM CDTSpecial Weather StatementGRBDoor, Marinette60 min
Aug 10, 7:49 PM CDTSpecial Marine WarningGRB86 min
Aug 10, 7:52 PM CDTSevere Thunderstorm WarningGRBCalumet, Kewaunee, Manitowoc38 min
Aug 10, 7:54 PM CDTTornado WarningGRBMarinette25 min
Aug 10, 10:05 PM CDTAreal Flood AdvisoryGRBBrown70 min
Aug 11, 3:11 AM CDTSmall Craft AdvisoryGRB19 hr
Aug 11, 11:25 AM CDTSpecial Weather StatementGRBOneida65 min
Aug 11, 11:54 AM CDTSpecial Weather StatementGRBLincoln, Marathon, Portage, Wood51 min
Aug 11, 12:18 PM CDTSevere Thunderstorm WarningGRBLincoln, Marathon42 min
Aug 11, 12:30 PM CDTSpecial Weather StatementGRBMarathon45 min
Aug 11, 12:38 PM CDTSevere Thunderstorm WarningGRBMarathon, Portage, Wood52 min
Aug 11, 12:42 PM CDTSpecial Weather StatementGRBFlorence, Forest33 min
Aug 11, 12:53 PM CDTSevere Thunderstorm WarningGRBFlorence, Forest, Marinette37 min
Aug 11, 12:57 PM CDTTornado WarningGRBLanglade, Lincoln, Marathon33 min
Aug 11, 1:04 PM CDTTornado WarningGRBMarathon41 min
Aug 11, 1:14 PM CDTSpecial Weather StatementGRBShawano46 min
Aug 11, 1:20 PM CDTSevere Thunderstorm WarningGRBLanglade, Lincoln, Marathon, Menominee, Shawano40 min
Aug 11, 1:24 PM CDTSevere Thunderstorm WarningGRBMarathon, Menominee, Portage, Shawano, Waupaca51 min
Aug 11, 1:31 PM CDTSevere Thunderstorm WarningGRBOconto, Shawano, Waupaca44 min
Aug 11, 1:40 PM CDTTornado WarningGRBMarathon20 min
Aug 11, 1:54 PM CDTAreal Flood AdvisoryGRBMarathon, Menominee, Shawano3 hr
Aug 11, 1:54 PM CDTSevere Thunderstorm WarningGRBPortage, Wood51 min
Aug 11, 2:07 PM CDTTornado WarningGRBBrown, Oconto, Shawano23 min
Aug 11, 2:16 PM CDTFlash Flood WarningGRBMarathon5 hr
Aug 11, 2:25 PM CDTSpecial Marine WarningGRB65 min
Aug 11, 2:27 PM CDTSevere Thunderstorm WarningGRBBrown, Oconto35 min
Aug 11, 2:37 PM CDTAreal Flood AdvisoryGRBMarinette, Oconto2 hr
Aug 11, 2:46 PM CDTSpecial Marine WarningGRB59 min
Aug 11, 2:47 PM CDTSevere Thunderstorm WarningGRBWaushara43 min
Aug 11, 2:47 PM CDTTornado WarningGRBMarathon43 min
Aug 11, 2:51 PM CDTSevere Thunderstorm WarningGRBBrown, Door, Kewaunee39 min
Aug 11, 2:55 PM CDTAreal Flood AdvisoryGRBDoor2 hr
Aug 11, 2:58 PM CDTSpecial Weather StatementGRBWaupaca47 min
Aug 11, 3:07 PM CDTFlash Flood WarningGRBMarathon4 hr
Aug 11, 3:08 PM CDTSevere Thunderstorm WarningGRBOutagamie, Shawano, Waupaca38 min
Aug 11, 3:11 PM CDTSpecial Marine WarningGRB64 min
Aug 11, 3:29 PM CDTSevere Thunderstorm Warning Considerable damage threatGRBWaushara18 min
Aug 11, 3:30 PM CDTSevere Thunderstorm WarningGRBBrown, Door, Kewaunee, Oconto, Outagamie, Shawano60 min
Aug 11, 3:33 PM CDTSpecial Marine WarningGRB57 min
Aug 11, 3:51 PM CDTSpecial Weather StatementGRBOutagamie, Winnebago39 min
Aug 11, 4:05 PM CDTSpecial Marine WarningGRB55 min

Nearby

Tornado Warnings in Wisconsin, 2021Every tornado warning in 2021Tornadoes in 2021

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.