Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 74, NWS Milwaukee, WI

September 7, 2021Racine County, Walworth County, Wisconsin

NWS Milwaukee, WI issued this severe thunderstorm warning at Sep 7, 2021, 12:19 PM CDT for Racine County, Walworth County, Wisconsin. It was in force for 40 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 7, 2021, 12:19 PM CDT (17:19 UTC)
Expired: Sep 7, 2021, 12:59 PM CDT
In force: 40 min
Issued by: NWS Milwaukee, WI
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Racine County, WI, Walworth County, WI

The radar

The Milwaukee radar (KMKX), 55 km from the middle of the area, began a volume at 17:21 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 7, 11:21 AM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 5.3 hours before the alert went out and 192 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: 14 J/kg
Mixed-layer CIN: -216 J/kg
Mixed-layer LCL: 1012 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: -120 m²/s²
0-3 km storm-relative helicity: 35 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.1

Open this sounding in Storm Lab

The text

As transmitted.

894 
WUUS53 KMKX 071719
SVRMKX
WIC101-127-071815-
/O.NEW.KMKX.SV.W.0074.210907T1719Z-210907T1815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Milwaukee/Sullivan WI
1219 PM CDT Tue Sep 7 2021

The National Weather Service in Milwaukee/Sullivan has issued a

* Severe Thunderstorm Warning for...
  Northeastern Walworth County in southeastern Wisconsin...
  Racine County in southeastern Wisconsin...

* Until 115 PM CDT.

* At 1219 PM CDT, a severe thunderstorm was located near East Troy,
  moving east at 50 mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Racine, Mount Pleasant, Sturtevant, Union Grove, East Troy, Wind
  Lake, Rochester, Raymond, Yorkville, Wind Point, Browns Lake,
  Waterford North, Potter Lake, Eagle Lake, Caledonia, Burlington,
  Waterford, Honey Creek, Elmwood Park and North Bay.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4276 8777 4270 8777 4267 8779 4267 8848
      4284 8846 4284 8782 4281 8778 4278 8775
TIME...MOT...LOC 1719Z 269DEG 64KT 4274 8847 

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

$$

GEHRING

2 follow-up statements

221 
WWUS53 KMKX 071751
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
1251 PM CDT Tue Sep 7 2021

WIC101-127-071815-
/O.CON.KMKX.SV.W.0074.000000T0000Z-210907T1815Z/
Walworth WI-Racine WI-
1251 PM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 PM CDT
FOR EAST CENTRAL WALWORTH AND RACINE COUNTIES...

At 1250 PM CDT, severe thunderstorms were located along a line 
extending from south of Oak Creek to 6 miles north of Lake Geneva, 
moving east at 45 mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Racine, Mount Pleasant, Sturtevant, Union Grove, Wind Lake,
Rochester, Raymond, Yorkville, Wind Point, Browns Lake, Eagle Lake,
Waterford North, Caledonia, Burlington, Waterford, Elmwood Park,
North Bay, Franksville, Kansasville and North Cape.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4276 8777 4270 8777 4267 8779 4267 8844
      4284 8812 4284 8782 4281 8778 4278 8775
TIME...MOT...LOC 1750Z 269DEG 40KT 4282 8790 4268 8839 

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

$$

GEHRING

537 
WWUS53 KMKX 071759
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
1259 PM CDT Tue Sep 7 2021

WIC101-127-071808-
/O.CAN.KMKX.SV.W.0074.000000T0000Z-210907T1815Z/
Walworth WI-Racine WI-
1259 PM CDT Tue Sep 7 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL WALWORTH AND
RACINE COUNTIES IS CANCELLED...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning has been cancelled.  However small hail and 
gusty winds are still possible with these thunderstorms especially 
toward the Kenosha County border.

A Severe Thunderstorm Watch remains in effect until 600 PM CDT for
southeastern Wisconsin.

LAT...LON 4276 8777 4270 8777 4267 8779 4267 8844
      4284 8812 4284 8782 4281 8778 4278 8775
TIME...MOT...LOC 1758Z 269DEG 64KT 4282 8770 4268 8819 

$$

GEHRING

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 6, 9:06 PM CDT	Small Craft Advisory	MKX		45 hr
Sep 7, 2:21 AM CDT	Gale Warning	MKX		13 hr
Sep 7, 8:41 AM CDT	Special Weather Statement	MKX	Marquette	49 min
Sep 7, 8:57 AM CDT	Severe Thunderstorm Warning	MKX	Green Lake, Marquette	48 min
Sep 7, 9:34 AM CDT	Severe Thunderstorm Warning	MKX	Fond du Lac	56 min
Sep 7, 10:10 AM CDT	Severe Thunderstorm Warning	MKX	Fond du Lac	50 min
Sep 7, 10:27 AM CDT	Severe Thunderstorm Warning	MKX	Fond du Lac, Sheboygan	78 min
Sep 7, 10:40 AM CDT	Special Weather Statement	MKX	Columbia, Dane, Dodge, Iowa	65 min
Sep 7, 10:57 AM CDT	Special Marine Warning	MKX		63 min
Sep 7, 11:01 AM CDT	Severe Thunderstorm Warning	MKX	Columbia, Dane, Dodge, Jefferson	59 min
Sep 7, 11:04 AM CDT	Severe Thunderstorm Warning	MKX	Dodge, Fond du Lac, Ozaukee, Sheboygan, Washington	56 min
Sep 7, 11:11 AM CDT	Severe Thunderstorm Warning	MKX	Green, Rock	34 min
Sep 7, 11:22 AM CDT	Special Marine Warning	MKX		53 min
Sep 7, 11:27 AM CDT	Severe Thunderstorm Warning	MKX	Milwaukee, Ozaukee, Washington, Waukesha	48 min
Sep 7, 11:31 AM CDT	Special Marine Warning	MKX		89 min
Sep 7, 11:42 AM CDT	Severe Thunderstorm Warning	MKX	Rock, Walworth	48 min
Sep 7, 11:45 AM CDT	Severe Thunderstorm Warning	MKX	Jefferson, Milwaukee, Waukesha	60 min
Sep 7, 12:18 PM CDT	Special Marine Warning	MKX		87 min
Sep 7, 12:30 PM CDT	Severe Thunderstorm Warning	MKX	Kenosha, Racine, Rock, Walworth	60 min
Sep 7, 12:47 PM CDT	Special Weather Statement	MKX	Milwaukee	28 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.