Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 10, NWS Milwaukee, WI

July 15, 2021Rock County, Walworth County, Wisconsin

NWS Milwaukee, WI issued this severe thunderstorm warning at Jul 15, 2021, 1:00 AM CDT for Rock County, Walworth County, Wisconsin. It was in force for 17 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: Jul 15, 2021, 1:00 AM CDT (06:00 UTC)
Expired: Jul 15, 2021, 1:17 AM CDT
In force: 17 min
Issued by: NWS Milwaukee, WI
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Rock County, WI, Walworth County, WI

The radar

The Milwaukee radar (KMKX), 48 km from the middle of the area, began a volume at 06:02 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

Davenport, (KDVN), launched 00:00Z, 6.0 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-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: 2569 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 832 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 253 m²/s²
0-3 km storm-relative helicity: 346 m²/s²
Significant tornado parameter: 3.2
Supercell composite: 23.4

Open this sounding in Storm Lab

The text

As transmitted.

965 
WUUS53 KMKX 150600
SVRMKX
WIC105-127-150630-
/O.NEW.KMKX.SV.W.0010.210715T0600Z-210715T0630Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Milwaukee/Sullivan WI
100 AM CDT Thu Jul 15 2021

The National Weather Service in Milwaukee/Sullivan has issued a

* Severe Thunderstorm Warning for...
  Western Walworth County in southeastern Wisconsin...
  Southeastern Rock County in south central Wisconsin...

* Until 130 AM CDT.

* At 1258 AM CDT, a severe thunderstorm was located over Clinton, or
  9 miles east of Beloit, moving east at 55 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Law Enforcement reported several trees and power lines 
           down across the Beloit area.

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

* Locations impacted include...
  Beloit, Elkhorn, Delavan, Williams Bay, Walworth, Clinton,
  Fontana-On-Geneva Lake, Sharon, Darien, Como, Richmond, Tiffany,
  Abells Corners, Tibbets, Allens Grove, Millard, Avalon, Shopiere,
  Emerald Grove and Johnstown Center.

People attending Elkhorn Ribfest should seek safe shelter
immediately!

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4250 8902 4265 8903 4279 8854 4250 8843
      4249 8871
TIME...MOT...LOC 0558Z 250DEG 49KT 4256 8886 

HAIL...<.75IN
WIND...60MPH
 
$$

KUROSKI

1 follow-up statement

901 
WWUS53 KMKX 150617
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
117 AM CDT Thu Jul 15 2021

WIC105-127-150627-
/O.CAN.KMKX.SV.W.0010.000000T0000Z-210715T0630Z/
Walworth WI-Rock WI-
117 AM CDT Thu Jul 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN WALWORTH AND
SOUTHEASTERN ROCK COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled. However gusty winds are 
still possible with this thunderstorm.

LAT...LON 4250 8902 4265 8903 4279 8854 4250 8843
      4249 8871
TIME...MOT...LOC 0615Z 250DEG 49KT 4265 8853 

$$

KUROSKI

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 14, 7:26 PM CDT	Special Weather Statement	MKX	Ozaukee	34 min
Jul 14, 9:12 PM CDT	Tornado Warning	MKX	Columbia, Marquette	33 min
Jul 14, 11:10 PM CDT	Areal Flood Advisory	MKX	Fond du Lac, Sheboygan	5 hr
Jul 15, 12:47 AM CDT	Special Weather Statement	MKX	Rock	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.