Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 20, NWS Milwaukee, WI

August 6, 2021Fond du Lac County, Sheboygan County, Wisconsin

NWS Milwaukee, WI issued this severe thunderstorm warning at Aug 6, 2021, 4:04 PM CDT for Fond du Lac County, Sheboygan County, Wisconsin. It was in force for 41 min. 1 report 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 6, 2021, 4:04 PM CDT (21:04 UTC)
Expired: Aug 6, 2021, 4:45 PM CDT
In force: 41 min
Issued by: NWS Milwaukee, WI
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Fond du Lac County, WI, Sheboygan County, WI

The radar

The Green Bay radar (KGRB), 79 km from the middle of the area, began a volume at 21:04 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

Time	Report	Where	Remark
Aug 6, 4:45 PM CDT	TSTM WND DMG	2 Wnw Plymouth, WI	RELAYED REPORT OF TREE DAMAGE IN PLYMOUTH. TIME ESTIMATED.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 9.1 hours before the alert went out and 76 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: 132 J/kg
Mixed-layer CIN: -114 J/kg
Mixed-layer LCL: 962 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 84 m²/s²
0-3 km storm-relative helicity: 98 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

417 
WUUS53 KMKX 062104
SVRMKX
WIC039-117-062145-
/O.NEW.KMKX.SV.W.0020.210806T2104Z-210806T2145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Milwaukee/Sullivan WI
404 PM CDT Fri Aug 6 2021

The National Weather Service in Milwaukee/Sullivan has issued a

* Severe Thunderstorm Warning for...
  East central Fond du Lac County in east central Wisconsin...
  Northwestern Sheboygan County in east central Wisconsin...

* Until 445 PM CDT.

* At 404 PM CDT, a severe thunderstorm was located 7 miles southwest
  of Elkhart Lake, or 8 miles west of Plymouth, moving northeast at
  15 mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Plymouth, Elkhart Lake, Greenbush, St. Cloud, Glenbeulah and Town
  of Forest.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4376 8792 4369 8815 4377 8826 4389 8810
      4389 8803
TIME...MOT...LOC 2104Z 228DEG 13KT 4377 8814 

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

$$

HANSEN

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 6, 3:06 PM CDT	Special Weather Statement	MKX	Calumet	24 min
Aug 6, 3:44 PM CDT	Special Weather Statement	MKX	Sheboygan	31 min
Aug 6, 3:48 PM CDT	Special Marine Warning	MKX		42 min
Aug 6, 4:09 PM CDT	Severe Thunderstorm Warning	MKX	Dodge, Fond du Lac	39 min
Aug 6, 4:21 PM CDT	Severe Thunderstorm Warning	MKX	Sheboygan	24 min
Aug 6, 4:23 PM CDT	Special Marine Warning	MKX		52 min
Aug 6, 4:38 PM CDT	Severe Thunderstorm Warning	MKX	Sheboygan	52 min
Aug 6, 4:41 PM CDT	Special Marine Warning	MKX		64 min
Aug 6, 4:58 PM CDT	Severe Thunderstorm Warning	MKX	Dodge, Jefferson	32 min
Aug 6, 5:06 PM CDT	Severe Thunderstorm Warning	MKX	Ozaukee, Sheboygan	24 min
Aug 6, 5:08 PM CDT	Special Marine Warning	MKX		52 min
Aug 6, 5:23 PM CDT	Special Marine Warning	MKX		111 min
Aug 6, 5:26 PM CDT	Special Weather Statement	MKX	Dodge, Ozaukee, Washington, Waukesha	94 min
Aug 6, 6:22 PM CDT	Severe Thunderstorm Warning	MKX	Jefferson	38 min
Aug 6, 6:53 PM CDT	Special Weather Statement	MKX	Jefferson, Milwaukee, Waukesha	82 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.