Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 78, NWS Milwaukee, WI

September 13, 2021Dane County, Jefferson County, Wisconsin

NWS Milwaukee, WI issued this severe thunderstorm warning at Sep 13, 2021, 1:55 AM CDT for Dane County, Jefferson County, Wisconsin. It was in force for 50 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 13, 2021, 1:55 AM CDT (06:55 UTC)
Expired
Sep 13, 2021, 2:45 AM CDT
In force
50 min
Issued by
NWS Milwaukee, WI
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Dane County, WI, Jefferson County, WI

The radar

The Milwaukee radar (KMKX), 51 km from the middle of the area, began a volume at 06:56 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 nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 6.9 hours before the alert went out and 176 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 00:00Z on 2021-09-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2021-09-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1081 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
105 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

789 
WUUS53 KMKX 130655
SVRMKX
WIC025-055-130745-
/O.NEW.KMKX.SV.W.0078.210913T0655Z-210913T0745Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Milwaukee/Sullivan WI
155 AM CDT Mon Sep 13 2021

The National Weather Service in Milwaukee/Sullivan has issued a

* Severe Thunderstorm Warning for...
  Southeastern Dane County in south central Wisconsin...
  Northwestern Jefferson County in southeastern Wisconsin...

* Until 245 AM CDT.

* At 155 AM CDT, a severe thunderstorm was located over southeastern
  Madison, moving east at 30 mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Madison, Sun Prairie, Fitchburg, Watertown, Fort Atkinson,
  Jefferson, McFarland, Monona, Lake Mills, Marshall, Waterloo,
  Cottage Grove, Johnson Creek, Deerfield, Shorewood Hills,
  Cambridge, Maple Bluff, Lake Ripley, Milford and Utica.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4313 8948 4320 8908 4320 8872 4294 8874
      4294 8942
TIME...MOT...LOC 0655Z 259DEG 28KT 4306 8932 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

BOXELL
2 follow-up statements
540 
WWUS53 KMKX 130713
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
213 AM CDT Mon Sep 13 2021

WIC025-055-130745-
/O.CON.KMKX.SV.W.0078.000000T0000Z-210913T0745Z/
Dane WI-Jefferson WI-
213 AM CDT Mon Sep 13 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 245 AM CDT
FOR EAST CENTRAL DANE AND NORTHWESTERN JEFFERSON COUNTIES...

At 213 AM CDT, a severe thunderstorm was located near Deerfield, or 7
miles southwest of Marshall, moving east at 30 mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Watertown, Jefferson, Lake Mills, Marshall, Waterloo, Cottage Grove,
Johnson Creek, Deerfield, Cambridge, Lake Ripley, Milford, Utica and
Rockdale.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4311 8929 4317 8908 4320 8872 4294 8874
      4297 8924
TIME...MOT...LOC 0713Z 260DEG 28KT 4307 8913 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

BOXELL
987 
WWUS53 KMKX 130734
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
234 AM CDT Mon Sep 13 2021

WIC025-130744-
/O.CAN.KMKX.SV.W.0078.000000T0000Z-210913T0745Z/
Dane WI-
234 AM CDT Mon Sep 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL DANE COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

An additional Severe Thunderstorm Warning remains in effect for 
western Dane County until 3 AM. 

LAT...LON 4318 8897 4317 8872 4310 8873 4299 8874
      4296 8901 4318 8901
TIME...MOT...LOC 0734Z 263DEG 28KT 4307 8890 

$$

WIC055-130745-
/O.CON.KMKX.SV.W.0078.000000T0000Z-210913T0745Z/
Jefferson WI-
234 AM CDT Mon Sep 13 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 245 AM CDT
FOR NORTHWESTERN JEFFERSON COUNTY...

At 234 AM CDT, a severe thunderstorm was located over Lake Mills,
moving east at 30 mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Jefferson, Lake Mills, Waterloo, Johnson Creek, Lake Ripley and
Milford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4318 8897 4317 8872 4310 8873 4299 8874
      4296 8901 4318 8901
TIME...MOT...LOC 0734Z 263DEG 28KT 4307 8890 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

BOXELL

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 13, 1:41 AM CDTSpecial Weather StatementMKXDane, Iowa34 min
Sep 13, 2:15 AM CDTSevere Thunderstorm WarningMKXDane, Iowa45 min
Sep 13, 2:38 AM CDTSevere Thunderstorm WarningMKXJefferson, Waukesha52 min
Sep 13, 2:45 AM CDTSevere Thunderstorm WarningMKXDane30 min
Sep 13, 3:15 AM CDTSpecial Weather StatementMKXJefferson30 min
Sep 13, 3:29 AM CDTSpecial Weather StatementMKXWaukesha31 min
Sep 13, 3:34 AM CDTSevere Thunderstorm WarningMKXMilwaukee, Waukesha41 min
Sep 13, 3:38 AM CDTSpecial Marine WarningMKX75 min
Sep 13, 6:11 AM CDTSevere Thunderstorm WarningMKXIowa, Sauk28 min
Sep 13, 7:43 AM CDTSpecial Weather StatementMKXJefferson32 min
Sep 13, 8:21 AM CDTSpecial Weather StatementMKXMilwaukee, Ozaukee, Washington, Waukesha39 min
Sep 13, 1:13 PM CDTSmall Craft AdvisoryMKX29 hr
Sep 13, 3:51 PM CDTSpecial Weather StatementMKXDodge39 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.