Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 97, NWS Green Bay, WI

December 15, 2021Marathon County, Wood County, Wisconsin

NWS Green Bay, WI issued this severe thunderstorm warning at Dec 15, 2021, 9:06 PM CST for Marathon County, Wood County, Wisconsin. It was in force for 54 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: Dec 15, 2021, 9:06 PM CST (03:06 UTC)
Expired: Dec 15, 2021, 10:00 PM CST
In force: 54 min
Issued by: NWS Green Bay, WI
Area: Storm-based polygon
Tornado: Possible
Damage threat: Considerable
Hail: 1.0 in
Wind: 70.0 mph

Counties Marathon County, WI, Wood County, WI

The radar

The La Crosse radar (KARX), 140 km from the middle of the area, began a volume at 03:10 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

Time	Report	Where	Remark
Dec 15, 9:37 PM CST	TSTM WND DMG	Colby, WI	TREE DAMAGE. SOCIAL MEDIA REPORT FROM WSAW-TV
Dec 15, 9:47 PM CST	TSTM WND GST 54	Marshfield, WI
Dec 15, 10:10 PM CST	TSTM WND DMG	Marathon City, WI	SEVERAL TREES DOWN IN MARATHON CITY

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.

Issued	Product	Office	Lasted
Dec 15, 5:30 PM CST	Tornado Watch	SPC	6 hr

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 3.1 hours before the alert went out and 166 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 29 J/kg
Mixed-layer CIN: -469 J/kg
Mixed-layer LCL: 505 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 689 m²/s²
0-3 km storm-relative helicity: 687 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

477 
WUUS53 KGRB 160306
SVRGRB
WIC073-141-160400-
/O.NEW.KGRB.SV.W.0097.211216T0306Z-211216T0400Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Green Bay WI
906 PM CST Wed Dec 15 2021

The National Weather Service in Green Bay has issued a

* Severe Thunderstorm Warning for...
  Wood County in central Wisconsin...
  Western Marathon County in central Wisconsin...

* Until 1000 PM CST.

* At 905 PM CST, severe thunderstorms were located along a line
  extending from near Augusta to near Hatfield to Westby, moving
  northeast at 70 mph.

  HAZARD...70 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect considerable 
           tree damage. Wind damage is also likely to mobile homes, 
           roofs, and outbuildings.

* Locations impacted include...
  Marshfield, Spencer, Abbotsford, Babcock and Pittsville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Intense thunderstorm lines can produce brief tornadoes and 
widespread significant wind damage. Although a tornado is not 
immediately likely, it is best to move to an interior room on the 
lowest floor of a building. These storms may cause serious injury 
and significant property damage.

A Tornado Watch remains in effect until 1100 PM CST for central
Wisconsin.

&&

LAT...LON 4503 9031 4504 9020 4512 9020 4512 8973
      4425 8994 4425 9032
TIME...MOT...LOC 0305Z 220DEG 58KT 4474 9107 4444 9070 4368 9087 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Kallas

4 follow-up statements

022 
WWUS53 KGRB 160319
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
919 PM CST Wed Dec 15 2021

WIC073-141-160400-
/O.CON.KGRB.SV.W.0097.000000T0000Z-211216T0400Z/
Wood WI-Marathon WI-
919 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 PM CST
FOR WOOD AND WESTERN MARATHON COUNTIES...

At 919 PM CST, severe thunderstorms were located along a line
extending from near Greenwood to near Loyal to 6 miles southeast of
Fort Mc Coy, moving northeast at 70 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

Locations impacted include...
Marshfield, Abbotsford, Spencer, Pittsville, Babcock, Nekoosa, Colby,
Stratford, Marathon City and Edgar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for central
Wisconsin.

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 4503 9031 4504 9020 4512 9020 4512 8973
      4425 8994 4425 9032
TIME...MOT...LOC 0319Z 217DEG 65KT 4479 9071 4465 9048 4394 9062 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Kallas

944 
WWUS53 KGRB 160333
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
933 PM CST Wed Dec 15 2021

WIC073-141-160400-
/O.CON.KGRB.SV.W.0097.000000T0000Z-211216T0400Z/
Wood WI-Marathon WI-
933 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 PM CST
FOR WOOD AND WESTERN MARATHON COUNTIES...

At 932 PM CST, severe thunderstorms were located along a line
extending from 7 miles north of Owen to near Spencer to 9 miles
northeast of Tomah, moving northeast at 65 mph.

HAZARD...70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Marshfield, Abbotsford, Spencer, Pittsville, Babcock, Nekoosa, Colby,
Stratford, Marathon City and Edgar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for central
Wisconsin.

Intense thunderstorm lines can produce brief tornadoes and 
widespread significant wind damage. Although a tornado is not 
immediately likely, it is best to move to an interior room on the 
lowest floor of a building. These storms may cause serious injury 
and significant property damage.

&&

LAT...LON 4503 9031 4504 9020 4512 9020 4512 8973
      4425 8994 4425 9032
TIME...MOT...LOC 0332Z 220DEG 57KT 4506 9056 4479 9030 4410 9040 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Kallas

537 
WWUS53 KGRB 160345
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
945 PM CST Wed Dec 15 2021

WIC073-141-160400-
/O.CON.KGRB.SV.W.0097.000000T0000Z-211216T0400Z/
Wood WI-Marathon WI-
945 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 PM CST
FOR WOOD AND WESTERN MARATHON COUNTIES...

At 945 PM CST, severe thunderstorms were located along a line
extending from Chelsea to 10 miles east of Colby to near Babcock to
near Elroy, moving northeast at 65 mph.

HAZARD...70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Marshfield, Abbotsford, Spencer, Pittsville, Babcock, Nekoosa, Colby,
Stratford, Marathon City and Edgar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for central
Wisconsin.

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 4503 9031 4504 9020 4512 9020 4512 8973
      4425 8994 4425 9032
TIME...MOT...LOC 0345Z 232DEG 50KT 4526 9031 4486 9012 4421 9018 4377
9032

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Kallas

211 
WWUS53 KGRB 160357
SVSGRB

Severe Weather Statement
National Weather Service Green Bay WI
957 PM CST Wed Dec 15 2021

WIC073-141-160406-
/O.EXP.KGRB.SV.W.0097.000000T0000Z-211216T0400Z/
Wood WI-Marathon WI-
957 PM CST Wed Dec 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR WOOD AND WESTERN MARATHON
COUNTIES WILL EXPIRE AT 1000 PM CST...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with these thunderstorms.

A Tornado Watch remains in effect until 1100 PM CST for central
Wisconsin.

A Severe Thunderstorm Watch remains in effect until 100 AM CST for
north central Wisconsin.

Remember, a Severe Thunderstorm Warning still remains in effect for
eastern Wood and Marathon Counties until 1100 PM CST.

LAT...LON 4503 9031 4504 9020 4512 9020 4512 8973
      4425 8994 4425 9032
TIME...MOT...LOC 0356Z 220DEG 58KT 4540 9015 4500 8996 4435 9002 4391
9016

$$

Kallas

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 15, 9:55 PM CST	Severe Thunderstorm Warning Considerable damage threat	GRB	Langlade, Lincoln, Marathon, Portage, Waushara, Wood	65 min
Dec 15, 10:45 PM CST	Severe Thunderstorm Warning Considerable damage threat	GRB	Forest, Langlade, Menominee, Oconto, Oneida, Shawano and 1 more	45 min
Dec 16, 3:28 AM CST	Gale Warning	GRB		16 hr
Dec 16, 8:09 AM CST	Wind Advisory	GRB	Brown, Calumet, Door, Florence, Forest, Kewaunee and 16 more	9 hr

Nearby

Severe Thunderstorm Warnings in Wisconsin, 2021 Every 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.