Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 93, NWS Green Bay, WI

September 7, 2021Brown County, Kewaunee County, Manitowoc County, Wisconsin

NWS Green Bay, WI issued this severe thunderstorm warning at Sep 7, 2021, 9:09 AM CDT for Brown County, Kewaunee County, Manitowoc County, Wisconsin. It was in force for 36 min. 3 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, 9:09 AM CDT (14:09 UTC)
Expired
Sep 7, 2021, 9:45 AM CDT
In force
36 min
Issued by
NWS Green Bay, WI
Area
Storm-based polygon
Hail
1.5 in
Wind
60.0 mph

Counties Brown County, WI, Kewaunee County, WI, Manitowoc County, WI

The radar

The Green Bay radar (KGRB), 35 km from the middle of the area, began a volume at 14:10 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, 9:27 AM CDTHAIL 1.754 Nw Two Creeks, WITHE HAIL CAUSED DAMAGE TO CARS.
Sep 7, 9:32 AM CDTHAIL 1.25Maribel, WIHIGHWAY NN AND HIGHWAY Z.
Sep 7, 9:37 AM CDTHAIL 1.252 Nne Wayside, WIREPORT FROM MPING.

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, 2.2 hours before the alert went out and 34 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°0°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.

374 
WUUS53 KGRB 071409
SVRGRB
WIC009-061-071-071445-
/O.NEW.KGRB.SV.W.0093.210907T1409Z-210907T1445Z/

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

The National Weather Service in Green Bay has issued a

* Severe Thunderstorm Warning for...
  Southeastern Brown County in northeastern Wisconsin...
  Southwestern Kewaunee County in northeastern Wisconsin...
  Northern Manitowoc County in east central Wisconsin...

* Until 945 AM CDT.

* At 908 AM CDT, a severe thunderstorm was located near Denmark, or 
  12 miles south of Green Bay, moving east at 55 mph. Ping pong ball 
  size hail was reported 1 mile north of Greenleaf at 904 am.

  HAZARD...Ping pong ball size hail and 60 mph wind gusts.

  SOURCE...Trained weather spotters.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           wind damage to roofs, siding, and trees.

* This severe thunderstorm will be near...
  Denmark around 915 AM CDT.

Other locations in the path of this severe thunderstorm include Two
Creeks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to shelter inside a strong building,  and stay away from
windows.

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

&&

LAT...LON 4444 8810 4450 8746 4444 8744 4443 8744
      4433 8748 4423 8747 4424 8808
TIME...MOT...LOC 1408Z 266DEG 46KT 4434 8797 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Cooley
2 follow-up statements
784 
WWUS53 KGRB 071422
SVSGRB

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

WIC009-061-071-071445-
/O.CON.KGRB.SV.W.0093.000000T0000Z-210907T1445Z/
Brown WI-Kewaunee WI-Manitowoc WI-
922 AM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 AM CDT
FOR SOUTHEASTERN BROWN...SOUTHWESTERN KEWAUNEE AND NORTHERN MANITOWOC
COUNTIES...

At 922 AM CDT, a severe thunderstorm was located near Two Creeks, or
13 miles southwest of Kewaunee, moving east at 55 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Trained weather spotters.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

Locations impacted include...
  Two Creeks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

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

&&

LAT...LON 4424 8808 4444 8810 4450 8746 4445 8744
      4433 8748 4423 8747
TIME...MOT...LOC 1422Z 268DEG 49KT 4432 8769 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

KLJ
718 
WWUS53 KGRB 071437
SVSGRB

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

WIC009-061-071-071445-
/O.CON.KGRB.SV.W.0093.000000T0000Z-210907T1445Z/
Brown WI-Kewaunee WI-Manitowoc WI-
937 AM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 AM CDT
FOR SOUTHEASTERN BROWN...SOUTHWESTERN KEWAUNEE AND NORTHERN MANITOWOC
COUNTIES...

At 937 AM CDT, a severe thunderstorm was located near Denmark, or 14
miles northwest of Manitowoc, moving east at 60 mph.

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

SOURCE...Trained weather spotters.

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

Locations impacted include...
Denmark, Two Creeks, Morrison, Mishicot, Larrabee, Cooperstown,
Glenmore, Hickory Grove, Maribel and Curran.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This storm is producing large hail. SEEK SHELTER NOW inside a sturdy
structure and stay away from windows.

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

&&

LAT...LON 4424 8808 4438 8810 4445 8744 4433 8748
      4423 8747
TIME...MOT...LOC 1437Z 268DEG 51KT 4428 8783 

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

$$

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, 9:16 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, 10:18 AM CDTSevere Thunderstorm WarningGRBCalumet, Manitowoc42 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.