Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 89, NWS Milwaukee, WI

December 15, 2021Iowa County, Lafayette County, Sauk County, Wisconsin

NWS Milwaukee, WI issued this severe thunderstorm warning at Dec 15, 2021, 9:28 PM CST for Iowa County, Lafayette County, Sauk County, Wisconsin. It was in force for 77 min. 5 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, 9:28 PM CST (03:28 UTC)
Expired
Dec 15, 2021, 10:45 PM CST
In force
77 min
Issued by
NWS Milwaukee, WI
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Iowa County, WI, Lafayette County, WI, Sauk County, WI

The radar

The La Crosse radar (KARX), 113 km from the middle of the area, began a volume at 03:32 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
Dec 15, 9:55 PM CSTTSTM WND GST 627 Wnw Spring Green, WI
Dec 15, 10:02 PM CSTNON-TSTM WND GST 666 Wnw Spring Green, WI
Dec 15, 10:10 PM CSTTSTM WND DMGDodgeville, WIPOWER LINES DOWN IN REWEY, DODGEVILLE AND COBB. POWER OUT IN BARNEVELD.
Dec 15, 10:11 PM CSTTSTM WND GST 561 Ne Dodgeville, WI
Dec 15, 10:46 PM CSTNON-TSTM WND GST 671 Ne Dodgeville, WI

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
Dec 15, 5:30 PM CSTTornado WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 3.5 hours before the alert went out and 194 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, Davenport, at 00:00Z on 2021-12-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 229 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, Davenport, at 00:00Z on 2021-12-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 433 square meters per square second.1939587897117Sfc1 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
229 J/kg
Mixed-layer CIN
-358 J/kg
Mixed-layer LCL
1061 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
433 m²/s²
0-3 km storm-relative helicity
496 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

699 
WUUS53 KMKX 160328
SVRMKX
WIC049-065-111-160445-
/O.NEW.KMKX.SV.W.0089.211216T0328Z-211216T0445Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Milwaukee/Sullivan WI
928 PM CST Wed Dec 15 2021

The National Weather Service in Milwaukee/Sullivan has issued a

* Severe Thunderstorm Warning for...
  Lafayette County in south central Wisconsin...
  Iowa County in south central Wisconsin...
  Sauk County in south central Wisconsin...

* Until 1045 PM CST.

* At 927 PM CST, severe thunderstorms were located along a line
  extending from near Tomah to 10 miles north of Boscobel to near
  Canton, moving northeast at 75 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Baraboo, Reedsburg, Dodgeville, Prairie Du Sac, Sauk City,
  Wisconsin Dells, Mineral Point, Darlington, Lake Delton, Spring
  Green, West Baraboo, Shullsburg, Belmont, Benton, Argyle,
  Blanchardville, Barneveld, Wiota, Highland and Arena.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A Tornado Watch remains in effect for the warned area. Tornadoes can
develop quickly from severe thunderstorms. Although a tornado is not
immediately likely, if one is spotted, act quickly and move to a
place of safety inside a sturdy structure such as a basement or small
interior room.


&&

LAT...LON 4320 9043 4321 9029 4317 9019 4355 9019
      4356 9031 4364 9031 4364 8979 4360 8976
      4360 8972 4357 8973 4356 8960 4338 8960
      4336 8967 4331 8973 4327 8972 4321 8984
      4251 8984 4251 9042
TIME...MOT...LOC 0327Z 223DEG 63KT 4405 9048 4329 9062 4221 9093 

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

$$

DDV
3 follow-up statements
656 
WWUS53 KMKX 160401
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
1001 PM CST Wed Dec 15 2021

WIC049-065-111-160445-
/O.CON.KMKX.SV.W.0089.000000T0000Z-211216T0445Z/
Lafayette WI-Iowa WI-Sauk WI-
1001 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 PM CST
FOR LAFAYETTE...IOWA AND SAUK COUNTIES...

At 958 PM CST, severe thunderstorms were located along a line
extending from near Wisconsin Rapids to 7 miles east of Wonewoc to
Benton, moving northeast at 75 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated. Recent report of 68 mph gust in 
         Platteville. 

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

Locations impacted include...
Baraboo, Reedsburg, Dodgeville, Prairie Du Sac, Sauk City, Wisconsin
Dells, Mineral Point, Darlington, Lake Delton, Spring Green, West
Baraboo, Shullsburg, Belmont, Benton, Argyle, Blanchardville,
Barneveld, Wiota, Arena and Plain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A Tornado Watch remains in effect until 1100 PM CST for south 
central Wisconsin. Tornadoes can develop quickly from severe 
thunderstorms. Although a tornado is not immediately likely, if one 
is spotted act quickly and move to a place of safety inside a sturdy 
structure, such as a basement or small interior room.

&&

LAT...LON 4299 9035 4321 9029 4317 9019 4355 9019
      4356 9031 4364 9031 4364 8979 4360 8976
      4360 8972 4357 8973 4356 8960 4338 8960
      4336 8967 4331 8973 4327 8972 4321 8984
      4251 8984 4251 9042
TIME...MOT...LOC 0358Z 226DEG 66KT 4442 8993 4366 9007 4259 9039 

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

$$

DDV
593 
WWUS53 KMKX 160420
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
1020 PM CST Wed Dec 15 2021

WIC049-065-111-160445-
/O.CON.KMKX.SV.W.0089.000000T0000Z-211216T0445Z/
Lafayette WI-Iowa WI-Sauk WI-
1020 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 PM CST
FOR LAFAYETTE...EASTERN IOWA AND SAUK COUNTIES...

At 1018 PM CST, severe thunderstorms were located along a line
extending from 9 miles south of Bevent to near Westfield to
Blanchardville, moving northeast at 100 mph.

HAZARD...60 mph wind gusts.

SOURCE...Emergency management reported power lines down in Iowa 
         County. Also getting reports of 50 to 65 mph gusts.

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

Locations impacted include...
Baraboo, Reedsburg, Prairie Du Sac, Sauk City, Wisconsin Dells,
Darlington, Lake Delton, West Baraboo, Shullsburg, Argyle,
Blanchardville, Barneveld, Wiota, Arena, Plain, Bluffview, North
Freedom, Ridgeway, New Diggings and South Wayne.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A tornado watch remains in effect for the warned area. Tornadoes can
develop quickly from severe thunderstorms. Although a tornado is not
immediately likely, if one is spotted act quickly and move to a place
of safety inside a sturdy structure, such as a basement or small
interior room.

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

&&

LAT...LON 4292 9002 4326 8998 4328 9019 4355 9019
      4356 9031 4364 9031 4364 8979 4360 8976
      4360 8972 4357 8973 4356 8960 4338 8960
      4336 8967 4331 8973 4327 8972 4321 8984
      4251 8984 4251 9042
TIME...MOT...LOC 0418Z 221DEG 87KT 4462 8938 4386 8953 4279 8985 

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

$$

DDV
518 
WWUS53 KMKX 160441
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
1041 PM CST Wed Dec 15 2021

WIC049-065-111-160450-
/O.EXP.KMKX.SV.W.0089.000000T0000Z-211216T0445Z/
Lafayette WI-Iowa WI-Sauk WI-
1041 PM CST Wed Dec 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR LAFAYETTE...EASTERN IOWA AND
SAUK COUNTIES WILL EXPIRE AT 1045 PM CST...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.

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

LAT...LON 4292 9002 4326 8998 4328 9019 4355 9019
      4356 9031 4364 9031 4364 8979 4360 8976
      4360 8972 4357 8973 4356 8960 4338 8960
      4336 8967 4331 8973 4327 8972 4321 8984
      4251 8984 4251 9042
TIME...MOT...LOC 0440Z 223DEG 63KT 4488 8904 4412 8920 4305 8952 

$$

DDV

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 16, 3:49 AM CSTGale WarningMKX19 hr
Dec 16, 8:49 AM CSTWind AdvisoryMKXColumbia, Dane, Dodge, Fond du Lac, Green Lake, Jefferson and 10 more8 hr

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.