Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 70, NWS Green Bay, WI

August 10, 2021Calumet County, Kewaunee County, Manitowoc County, Wisconsin

NWS Green Bay, WI issued this severe thunderstorm warning at Aug 10, 2021, 7:52 PM CDT for Calumet County, Kewaunee County, Manitowoc County, Wisconsin. It was in force for 38 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
Aug 10, 2021, 7:52 PM CDT (00:52 UTC)
Expired
Aug 10, 2021, 8:30 PM CDT
In force
38 min
Issued by
NWS Green Bay, WI
Area
Storm-based polygon
Tornado
Possible
Hail
1.0 in
Wind
60.0 mph

Counties Calumet County, WI, Kewaunee County, WI, Manitowoc County, WI

The radar

The Green Bay radar (KGRB), 39 km from the middle of the area, began a volume at 00:51 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 10, 8:02 PM CDTTSTM WND GST 39Manitowoc, WI
Aug 10, 8:13 PM CDTTSTM WND DMGManitowoc, WIFEW TREES DOWN ON POWER LINES.

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 10, 3:47 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 0.9 hours before the alert went out and 368 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, Davenport, at 00:00Z on 2021-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 856 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, Davenport, at 00:00Z on 2021-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 77 square meters per square second.193958Sfc1 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
856 J/kg
Mixed-layer CIN
-155 J/kg
Mixed-layer LCL
940 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
77 m²/s²
0-3 km storm-relative helicity
160 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-1.4

Open this sounding in Storm Lab

The text

As transmitted.

802 
WUUS53 KGRB 110052
SVRGRB
WIC015-061-071-110130-
/O.NEW.KGRB.SV.W.0070.210811T0052Z-210811T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Green Bay WI
752 PM CDT Tue Aug 10 2021

The National Weather Service in Green Bay has issued a

* Severe Thunderstorm Warning for...
  Kewaunee County in northeastern Wisconsin...
  Southeastern Calumet County in east central Wisconsin...
  Manitowoc County in east central Wisconsin...

* Until 830 PM CDT.

* At 752 PM CDT, severe thunderstorms were located along a line
  extending from near Kewaunee to 7 miles southeast of Denmark to
  Valders to near Camp Rokilio Scout Camp, moving east at 30 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Manitowoc, Kewaunee, Luxemburg, Cleveland, Valders, St. Nazianz,
  Two Creeks, Camp Rokilio Scout Camp, Two Rivers and Kiel.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

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

&&

LAT...LON 4403 8812 4424 8796 4424 8789 4433 8789
      4433 8777 4451 8776 4454 8774 4460 8737
      4454 8741 4433 8748 4418 8746 4407 8760
      4390 8769 4389 8811
TIME...MOT...LOC 0052Z 255DEG 25KT 4450 8744 4427 8772 4405 8785 4388
8797

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Kieckbusch
4 follow-up statements
041 
WWUS53 KGRB 110104
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
804 PM CDT Tue Aug 10 2021

WIC015-061-071-110130-
/O.CON.KGRB.SV.W.0070.000000T0000Z-210811T0130Z/
Kewaunee WI-Calumet WI-Manitowoc WI-
804 PM CDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR KEWAUNEE...SOUTHEASTERN CALUMET AND MANITOWOC COUNTIES...

At 803 PM CDT, a severe thunderstorm was located 3 miles west of Two 
Rivers, moving east at 45 mph. Large hail was likely occurring over 
northern Manitowoc County.

HAZARD...60 mph wind gusts and half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Manitowoc, Kewaunee, Luxemburg, Cleveland, Valders, St. Nazianz, Two
Creeks, Camp Rokilio Scout Camp, Two Rivers and Kiel.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Green Bay.

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

&&

LAT...LON 4403 8812 4424 8796 4424 8789 4433 8789
      4433 8777 4451 8776 4454 8774 4460 8737
      4454 8741 4433 8748 4418 8746 4407 8760
      4390 8769 4389 8811
TIME...MOT...LOC 0103Z 277DEG 40KT 4418 8764 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$
Kieckbusch
723 
WWUS53 KGRB 110112
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
812 PM CDT Tue Aug 10 2021

WIC015-110122-
/O.CAN.KGRB.SV.W.0070.000000T0000Z-210811T0130Z/
Calumet WI-
812 PM CDT Tue Aug 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CALUMET COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
northeastern and east central Wisconsin.

LAT...LON 4406 8793 4424 8796 4424 8789 4433 8789
      4433 8777 4451 8776 4454 8741 4432 8748
      4418 8746 4407 8760 4390 8769
TIME...MOT...LOC 0112Z 255DEG 25KT 4420 8755 

$$

WIC061-071-110130-
/O.CON.KGRB.SV.W.0070.000000T0000Z-210811T0130Z/
Kewaunee WI-Manitowoc WI-
812 PM CDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR SOUTHWESTERN KEWAUNEE AND MANITOWOC COUNTIES...

At 812 PM CDT, a severe thunderstorm was located near Two Creeks, or
9 miles northeast of Manitowoc, moving east at 30 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Manitowoc, Kewaunee, Cleveland, Valders, Two Creeks, Two Rivers,
Newton, Cato, Mishicot and Larrabee.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Green Bay.

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

&&

LAT...LON 4406 8793 4424 8796 4424 8789 4433 8789
      4433 8777 4451 8776 4454 8741 4432 8748
      4418 8746 4407 8760 4390 8769
TIME...MOT...LOC 0112Z 255DEG 25KT 4420 8755 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Kieckbusch
416 
WWUS53 KGRB 110121
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
821 PM CDT Tue Aug 10 2021

WIC061-110130-
/O.CAN.KGRB.SV.W.0070.000000T0000Z-210811T0130Z/
Kewaunee WI-
821 PM CDT Tue Aug 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN KEWAUNEE COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has weakened.
Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
east central Wisconsin.

LAT...LON 4414 8770 4430 8768 4432 8766 4433 8751
      4432 8748 4431 8748 4418 8746 4408 8759
      4405 8761
TIME...MOT...LOC 0120Z 272DEG 18KT 4421 8751 

$$

WIC071-110130-
/O.CON.KGRB.SV.W.0070.000000T0000Z-210811T0130Z/
Manitowoc WI-
821 PM CDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR NORTHEASTERN MANITOWOC COUNTY...

At 820 PM CDT, a severe thunderstorm was located near Two Creeks, or 
11 miles northeast of Manitowoc, moving east at 20 mph. Trees were 
reported to be down in Manitowoc.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Manitowoc, Two Creeks, Two Rivers, Mishicot, Point Beach State Park,
Fisherville, Point Beach Nuclear Plant and Shoto.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Green Bay.

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

&&

LAT...LON 4414 8770 4430 8768 4432 8766 4433 8751
      4432 8748 4431 8748 4418 8746 4408 8759
      4405 8761
TIME...MOT...LOC 0120Z 272DEG 18KT 4421 8751 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Kieckbusch
416 
WWUS53 KGRB 110125
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
825 PM CDT Tue Aug 10 2021

WIC071-110134-
/O.EXP.KGRB.SV.W.0070.000000T0000Z-210811T0130Z/
Manitowoc WI-
825 PM CDT Tue Aug 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MANITOWOC COUNTY
WILL EXPIRE AT 830 PM CDT...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.  However heavy rain is still possible with this
thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
east central Wisconsin.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Green Bay.

LAT...LON 4414 8770 4430 8768 4432 8766 4433 8751
      4432 8748 4431 8748 4418 8746 4408 8759
      4405 8761
TIME...MOT...LOC 0124Z 255DEG 25KT 4422 8748 

$$

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, 7:54 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, 2:09 PM CDTTornado Warning Tornado observedGRBMarathon51 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

Severe Thunderstorm Warnings in Wisconsin, 2021Every severe thunderstorm warning 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.