Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 104, NWS La Crosse, WI

September 20, 20214 counties in Wisconsin

NWS La Crosse, WI issued this severe thunderstorm warning at Sep 20, 2021, 7:41 PM CDT for 4 counties in Wisconsin. It was in force for 34 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Sep 20, 2021, 7:41 PM CDT (00:41 UTC)
Expired: Sep 20, 2021, 8:15 PM CDT
In force: 34 min
Issued by: NWS La Crosse, WI
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Juneau County, WI, Monroe County, WI, Richland County, WI, Vernon County, WI

The radar

The La Crosse radar (KARX), 78 km from the middle of the area, began a volume at 00:41 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Sep 20, 2:07 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 0.7 hours before the alert went out and 195 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: 429 J/kg
Mixed-layer CIN: -23 J/kg
Mixed-layer LCL: 735 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 194 m²/s²
0-3 km storm-relative helicity: 212 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 2.0

Open this sounding in Storm Lab

The text

As transmitted.

357 
WUUS53 KARX 210041
SVRARX
WIC057-081-103-123-210115-
/O.NEW.KARX.SV.W.0104.210921T0041Z-210921T0115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service La Crosse WI
741 PM CDT Mon Sep 20 2021

The National Weather Service in La Crosse has issued a

* Severe Thunderstorm Warning for...
  Southern Juneau County in central Wisconsin...
  Northeastern Vernon County in southwestern Wisconsin...
  Northeastern Richland County in southwestern Wisconsin...
  Southeastern Monroe County in west central Wisconsin...

* Until 815 PM CDT.

* At 740 PM CDT, severe thunderstorms were located along a line
  extending from 10 miles west of Elroy to Hillsboro to 11 miles
  southwest of Wonewoc, moving northeast at 55 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Severe thunderstorms will be near...
  Wonewoc around 745 PM CDT.
  Elroy around 750 PM CDT.
  Mauston around 755 PM CDT.
  New Lisbon around 800 PM CDT.

Other locations impacted by these severe thunderstorms include
Bartons Corners, Dells Timberland Campground, Bunker Hill, Johnson
Hill, Lyndon Station, Germantown and Glendale.

This includes Interstate 90/94 between mile markers 59 and 80.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4364 9031 4356 9031 4355 9019 4351 9019
      4345 9035 4358 9057 4368 9057 4396 9011
      4387 8997 4365 8983
TIME...MOT...LOC 0040Z 237DEG 49KT 4370 9047 4368 9032 4350 9031 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Skow

4 follow-up statements

257 
WWUS53 KARX 210052
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
752 PM CDT Mon Sep 20 2021

WIC057-081-103-123-210115-
/O.CON.KARX.SV.W.0104.000000T0000Z-210921T0115Z/
Juneau WI-Vernon WI-Richland WI-Monroe WI-
752 PM CDT Mon Sep 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM CDT
FOR SOUTHERN JUNEAU...NORTHEASTERN VERNON...NORTHEASTERN RICHLAND AND
SOUTHEASTERN MONROE COUNTIES...

At 751 PM CDT, severe thunderstorms were located along a line
extending from Elroy to near Wonewoc to 6 miles west of Reedsburg,
moving northeast at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe storms will be near...
  Mauston and New Lisbon around 805 PM CDT.

Other locations impacted by these severe thunderstorms include
Arrowhead Resort Campground, Dells Timberland Campground, Lindina,
Union Center, Bunker Hill, Cazenovia and Johnson Hill.

This includes Interstate 90/94 between mile markers 59 and 80.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4364 9031 4356 9031 4355 9019 4351 9019
      4345 9035 4361 9035 4370 9051 4396 9011
      4387 8997 4365 8983
TIME...MOT...LOC 0051Z 239DEG 48KT 4374 9030 4372 9015 4354 9014 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Skow

346 
WWUS53 KARX 210059
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
759 PM CDT Mon Sep 20 2021

WIC081-103-123-210109-
/O.CAN.KARX.SV.W.0104.000000T0000Z-210921T0115Z/
Vernon WI-Richland WI-Monroe WI-
759 PM CDT Mon Sep 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN VERNON...
NORTHEASTERN RICHLAND AND SOUTHEASTERN MONROE COUNTIES IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 4364 9031 4380 9031 4393 9007 4387 8997
      4365 8983
TIME...MOT...LOC 0059Z 237DEG 49KT 4380 9018 4378 9003 4360 9002 

$$

WIC057-210115-
/O.CON.KARX.SV.W.0104.000000T0000Z-210921T0115Z/
Juneau WI-
759 PM CDT Mon Sep 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM CDT
FOR SOUTHERN JUNEAU COUNTY...

At 759 PM CDT, severe thunderstorms were located along a line
extending from near New Lisbon to near Mauston to near Reedsburg,
moving northeast at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe thunderstorms will remain over mainly rural areas of
southern Juneau County, including the following locations...
Arrowhead Resort Campground, Dells Timberland Campground, Lindina,
Union Center, Johnson Hill, Lyndon Station and Bass Lake Campground.

This includes Interstate 90/94 between mile markers 62 and 80.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4364 9031 4380 9031 4393 9007 4387 8997
      4365 8983
TIME...MOT...LOC 0059Z 237DEG 49KT 4380 9018 4378 9003 4360 9002 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Skow

312 
WWUS53 KARX 210107
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
807 PM CDT Mon Sep 20 2021

WIC057-210115-
/O.CON.KARX.SV.W.0104.000000T0000Z-210921T0115Z/
Juneau WI-
807 PM CDT Mon Sep 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM CDT
FOR SOUTHERN JUNEAU COUNTY...

At 807 PM CDT, severe thunderstorms were located along a line
extending from near Mauston to 9 miles south of Dellwood to 7 miles
west of Wisconsin Dells, moving northeast at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Mauston, New Lisbon, Lemonweir, Lindina, Lyndon Station, Arrowhead
Resort Campground, Highway 58 And County G, Dells Timberland
Campground, Yukon Trails Campground, Bass Hollow Rec Area and Bass
Lake Campground.

This includes Interstate 90/94 between mile markers 62 and 80.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4364 9010 4384 9022 4393 9007 4387 8997
      4365 8983
TIME...MOT...LOC 0107Z 237DEG 49KT 4385 9008 4383 8993 4365 8992 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Skow

523 
WWUS53 KARX 210115
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
815 PM CDT Mon Sep 20 2021

WIC057-210125-
/O.EXP.KARX.SV.W.0104.000000T0000Z-210921T0115Z/
Juneau WI-
815 PM CDT Mon Sep 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN JUNEAU COUNTY HAS
EXPIRED...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been allowed to expire.

LAT...LON 4364 9010 4384 9022 4393 9007 4387 8997
      4365 8983
TIME...MOT...LOC 0115Z 237DEG 49KT 4390 8996 4388 8981 4370 8980 

$$

Skow

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 20, 7:01 PM CDT	Special Weather Statement	ARX	Crawford, Grant, Juneau, Monroe, Richland, Vernon	44 min
Sep 20, 7:17 PM CDT	Tornado Warning	ARX	Richland, Vernon	28 min
Sep 20, 7:20 PM CDT	Severe Thunderstorm Warning	ARX	Crawford, Grant, Richland	40 min
Sep 20, 7:48 PM CDT	Special Weather Statement	ARX	Grant	27 min
Sep 20, 7:58 PM CDT	Severe Thunderstorm Warning	ARX	Adams, Juneau	47 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.