Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 80, NWS La Crosse, WI

August 11, 2021Juneau County, Monroe County, Wisconsin

NWS La Crosse, WI issued this severe thunderstorm warning at Aug 11, 2021, 1:41 PM CDT for Juneau County, Monroe County, Wisconsin. It was in force for 64 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
Aug 11, 2021, 1:41 PM CDT (18:41 UTC)
Expired
Aug 11, 2021, 2:45 PM CDT
In force
64 min
Issued by
NWS La Crosse, WI
Area
Storm-based polygon
Tornado
Possible
Hail
1.25 in
Wind
60.0 mph

Counties Juneau County, WI, Monroe County, WI

The radar

The La Crosse radar (KARX), 69 km from the middle of the area, began a volume at 18:43 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 11, 1:55 PM CDTTSTM WND GST 41Camp Douglas, WIAWOS STATION KVOK VOLK FIELD.
Aug 11, 1:58 PM CDTHAIL 11 Wnw Clifton, WI
Aug 11, 2:08 PM CDTTORNADO2 Wsw Clifton, WITORNADO REPORTED ONGOING ALONG KIRKWOOD AVE. REPORTED A DESTROYED BARN.

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 11, 12:17 PM CDTTornado WatchSPC8 hr

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 6.7 hours before the alert went out and 193 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 2021-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1499 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 2021-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 156 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
1499 J/kg
Mixed-layer CIN
-136 J/kg
Mixed-layer LCL
678 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
156 m²/s²
0-3 km storm-relative helicity
206 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

As transmitted.

304 
WUUS53 KARX 111841
SVRARX
WIC057-081-111945-
/O.NEW.KARX.SV.W.0080.210811T1841Z-210811T1945Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service La Crosse WI
141 PM CDT Wed Aug 11 2021

The National Weather Service in La Crosse has issued a

* Severe Thunderstorm Warning for...
  Southwestern Juneau County in central Wisconsin...
  Southeastern Monroe County in west central Wisconsin...

* Until 245 PM CDT.

* At 140 PM CDT, a severe thunderstorm was located 9 miles southwest
  of Tomah, moving east at 25 mph.

  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...
  Sparta, Tomah, Mauston, New Lisbon, Elroy, Cashton, Norwalk, Camp 
  Douglas, Wilton, Ridgeville, Kendall, Oakdale, Wyeville and 
  Melvina.

This includes the following highways...
 Interstate 94 between mile markers 143 and 147.
 Interstate 90/94 between mile markers 46 and 72.
 Interstate 90 in Wisconsin between mile markers 27 and 45.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM CDT for central,
southwestern and west central Wisconsin.

Prepare immediately for large hail and damaging winds. People outside
should move immediately to shelter inside a strong building. 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.
Hustler, A Tornado Watch remains in effect until 800 PM CDT for 
central, southwestern and west central Wisconsin.

&&

LAT...LON 4371 8999 4372 9031 4373 9031 4373 9078
      4399 9080 4409 9013
TIME...MOT...LOC 1840Z 271DEG 23KT 4388 9062 

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

$$

DTJ
1 follow-up statement
203 
WWUS53 KARX 111926
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
226 PM CDT Wed Aug 11 2021

WIC057-081-111945-
/O.CON.KARX.SV.W.0080.000000T0000Z-210811T1945Z/
Juneau WI-Monroe WI-
226 PM CDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 245 PM CDT
FOR WEST CENTRAL JUNEAU AND SOUTHEASTERN MONROE COUNTIES...

At 225 PM CDT, a severe thunderstorm was located near Sparta, moving
east at 40 mph.

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...
Sparta, Tomah, Cashton, Glendale, Norwalk, Wilton, Ridgeville,
Kendall, Clifton, Oakdale, Wyeville, Melvina, Oil City, St Marys,
Jackson Pass, Tunnel City, Highway 131 And County A, Mill Bluff State
Park, Hoffman Corners and Shennington.

This includes the following highways...
 Interstate 94 between mile markers 143 and 147.
 Interstate 90/94 between mile markers 46 and 52.
 Interstate 90 in Wisconsin between mile markers 27 and 45.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM CDT for central,
southwestern and west central Wisconsin.

Prepare immediately for large hail and damaging winds. 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 4372 9031 4373 9031 4373 9078 4399 9080
      4406 9030
TIME...MOT...LOC 1925Z 278DEG 34KT 4388 9073 

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

$$

JSB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 10, 9:19 PM CDTRiver Flood WarningARXLa Crosse, Trempealeau30 hr
Aug 11, 11:32 AM CDTSpecial Weather StatementARXTaylor28 min
Aug 11, 11:57 AM CDTSpecial Weather StatementARXClark, Taylor33 min
Aug 11, 12:18 PM CDTSevere Thunderstorm WarningARXTaylor42 min
Aug 11, 12:31 PM CDTSpecial Weather StatementARXClark, Jackson, La Crosse, Monroe59 min
Aug 11, 1:01 PM CDTTornado WarningARXClark17 min
Aug 11, 1:07 PM CDTSevere Thunderstorm WarningARXLa Crosse, Monroe38 min
Aug 11, 1:48 PM CDTTornado WarningARXJuneau, Monroe42 min
Aug 11, 2:06 PM CDTSevere Thunderstorm WarningARXLa Crosse, Monroe39 min
Aug 11, 2:18 PM CDTSevere Thunderstorm WarningARXLa Crosse, Monroe, Vernon42 min
Aug 11, 2:20 PM CDTTornado Warning Tornado observedConsiderable damage threatARXAdams, Juneau, Monroe55 min
Aug 11, 2:32 PM CDTSevere Thunderstorm WarningARXMonroe28 min
Aug 11, 3:06 PM CDTSevere Thunderstorm WarningARXRichland, Vernon54 min
Aug 11, 4:19 PM CDTSpecial Weather StatementARXGrant26 min
Aug 11, 4:23 PM CDTSevere Thunderstorm WarningARXGrant22 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.