Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 96, NWS Green Bay, WI

September 7, 2021Calumet County, Manitowoc County, Wisconsin

NWS Green Bay, WI issued this severe thunderstorm warning at Sep 7, 2021, 10:18 AM CDT for Calumet County, Manitowoc County, Wisconsin. It was in force for 42 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
Sep 7, 2021, 10:18 AM CDT (15:18 UTC)
Expired
Sep 7, 2021, 11:00 AM CDT
In force
42 min
Issued by
NWS Green Bay, WI
Area
Storm-based polygon
Hail
1.25 in
Wind
50.0 mph

Counties Calumet County, WI, Manitowoc County, WI

The radar

The Green Bay radar (KGRB), 59 km from the middle of the area, began a volume at 15:21 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
Sep 7, 10:25 AM CDTHAIL 18 Ese Valders, WI
Sep 7, 10:48 AM CDTHAIL 1.251 Se Cleveland, WIREPORT RECEIVED VIA SOCIAL MEDIA.

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

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 3.3 hours before the alert went out and 56 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 2021-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 14 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 2021-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -120 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
14 J/kg
Mixed-layer CIN
-216 J/kg
Mixed-layer LCL
1012 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
-120 m²/s²
0-3 km storm-relative helicity
35 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

As transmitted.

440 
WUUS53 KGRB 071518
SVRGRB
WIC015-071-071600-
/O.NEW.KGRB.SV.W.0096.210907T1518Z-210907T1600Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Green Bay WI
1018 AM CDT Tue Sep 7 2021

The National Weather Service in Green Bay has issued a

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

* Until 1100 AM CDT.

* At 1016 AM CDT, a severe thunderstorm was located near Chilton, or 
  18 miles northwest of Plymouth, moving east at 55 mph. At 1004 am 
  half dollar size hail was reported near Chilton. Another severe 
  storm was located near St Nazianz.

  HAZARD...Half dollar size hail.

  SOURCE...Public.

  IMPACT...Damage to vehicles is expected.

* This severe thunderstorm will be near...
  St. Nazianz and Camp Rokilio Scout Camp around 1025 AM CDT.
  Valders around 1030 AM CDT.
  Cleveland around 1035 AM CDT.

Other locations in the path of this severe thunderstorm include
Manitowoc.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4394 8816 4394 8822 4406 8818 4412 8754
      4407 8760 4390 8769 4389 8816
TIME...MOT...LOC 1516Z 264DEG 49KT 4399 8811 

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

$$

Cooley
3 follow-up statements
956 
WWUS53 KGRB 071532
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
1032 AM CDT Tue Sep 7 2021

WIC015-071-071600-
/O.CON.KGRB.SV.W.0096.000000T0000Z-210907T1600Z/
Calumet WI-Manitowoc WI-
1032 AM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 AM CDT
FOR SOUTHEASTERN CALUMET AND SOUTHWESTERN MANITOWOC COUNTIES...

At 1031 AM CDT, a severe thunderstorm was located near Cleveland, or
8 miles north of Howards Grove, moving east at 50 mph.

HAZARD...Half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Manitowoc, Cleveland, Valders, St. Nazianz, St Anna, Camp Rokilio
Scout Camp, Kiel, New Holstein, Newton and Spring Valley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

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

&&

LAT...LON 4394 8816 4394 8821 4408 8797 4412 8754
      4406 8761 4390 8769 4389 8816
TIME...MOT...LOC 1531Z 267DEG 45KT 4395 8783 

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

$$

KLJ
973 
WWUS53 KGRB 071542
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
1042 AM CDT Tue Sep 7 2021

WIC015-071551-
/O.CAN.KGRB.SV.W.0096.000000T0000Z-210907T1600Z/
Calumet WI-
1042 AM CDT Tue Sep 7 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.

LAT...LON 4391 8804 4409 8786 4412 8754 4405 8761
      4390 8769 4389 8804
TIME...MOT...LOC 1541Z 264DEG 49KT 4396 8763 

$$

WIC071-071600-
/O.CON.KGRB.SV.W.0096.000000T0000Z-210907T1600Z/
Manitowoc WI-
1042 AM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 AM CDT
FOR SOUTHWESTERN MANITOWOC COUNTY...

At 1041 AM CDT, a severe thunderstorm was located near Cleveland, or
9 miles south of Manitowoc, moving east at 55 mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Manitowoc, Cleveland, Valders, St. Nazianz, Camp Rokilio Scout Camp,
Kiel, Newton, Spring Valley, Clover and Louis Corners.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

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

&&

LAT...LON 4391 8804 4409 8786 4412 8754 4405 8761
      4390 8769 4389 8804
TIME...MOT...LOC 1541Z 264DEG 49KT 4396 8763 

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

$$

KLJ
014 
WWUS53 KGRB 071551
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
1051 AM CDT Tue Sep 7 2021

WIC071-071601-
/O.EXP.KGRB.SV.W.0096.000000T0000Z-210907T1600Z/
Manitowoc WI-
1051 AM CDT Tue Sep 7 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN MANITOWOC COUNTY
WILL EXPIRE AT 1100 AM CDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

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

LAT...LON 4391 8804 4409 8786 4412 8754 4405 8761
      4390 8769 4389 8804
TIME...MOT...LOC 1551Z 264DEG 49KT 4397 8749 

$$

KLJ

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 2:16 AM CDTSpecial Weather StatementGRBVilas89 min
Sep 7, 3:08 AM CDTSpecial Weather StatementGRBVilas97 min
Sep 7, 3:38 AM CDTSpecial Weather StatementGRBOneida, Vilas67 min
Sep 7, 4:22 AM CDTSpecial Weather StatementGRBFlorence, Forest, Langlade, Lincoln38 min
Sep 7, 5:23 AM CDTSpecial Weather StatementGRBMarinette, Menominee, Oconto52 min
Sep 7, 6:09 AM CDTSpecial Weather StatementGRBDoor, Oconto51 min
Sep 7, 6:17 AM CDTSpecial Marine WarningGRB88 min
Sep 7, 8:04 AM CDTSpecial Weather StatementGRBOutagamie, Waupaca41 min
Sep 7, 8:11 AM CDTSevere Thunderstorm WarningGRBOutagamie, Waupaca49 min
Sep 7, 8:16 AM CDTSpecial Marine WarningGRB59 min
Sep 7, 8:28 AM CDTSpecial Weather StatementGRBKewaunee62 min
Sep 7, 8:42 AM CDTSpecial Marine WarningGRB63 min
Sep 7, 8:42 AM CDTSevere Thunderstorm WarningGRBBrown, Outagamie48 min
Sep 7, 9:02 AM CDTSevere Thunderstorm WarningGRBWaushara, Winnebago43 min
Sep 7, 9:09 AM CDTSevere Thunderstorm WarningGRBBrown, Kewaunee, Manitowoc36 min
Sep 7, 9:16 AM CDTSevere Thunderstorm WarningGRBBrown, Calumet, Manitowoc, Outagamie, Winnebago44 min
Sep 7, 9:19 AM CDTSpecial Marine WarningGRB86 min
Sep 7, 9:30 AM CDTSevere Thunderstorm WarningGRBCalumet, Manitowoc, Winnebago60 min
Sep 7, 9:48 AM CDTSpecial Weather StatementGRBKewaunee27 min
Sep 7, 10:23 AM CDTSpecial Marine WarningGRB52 min
Sep 7, 11:14 AM CDTSpecial Marine WarningGRB26 min
Sep 7, 6:05 PM CDTSpecial Weather StatementGRBOneida, Vilas40 min
Sep 7, 6:44 PM CDTSpecial Weather StatementGRBForest, Oneida46 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.