Alert archive / Wisconsin / Tornado Warnings in 2021

Tornado Warning 14, NWS Milwaukee, WI

August 11, 2021Dane County, Wisconsin

NWS Milwaukee, WI issued this tornado warning at Aug 11, 2021, 6:34 PM CDT for Dane County, Wisconsin. It was in force for 15 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: Aug 11, 2021, 6:34 PM CDT (23:34 UTC)
Expired: Aug 11, 2021, 6:49 PM CDT
In force: 15 min
Issued by: NWS Milwaukee, WI
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Dane County, WI

The radar

The Milwaukee radar (KMKX), 94 km from the middle of the area, began a volume at 23:38 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
Aug 11, 12:17 PM CDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.6 hours before the alert went out and 161 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: 2852 J/kg
Mixed-layer CIN: -107 J/kg
Mixed-layer LCL: 1040 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 170 m²/s²
0-3 km storm-relative helicity: 193 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.7

Open this sounding in Storm Lab

The text

As transmitted.

229 
WFUS53 KMKX 112334
TORMKX
WIC025-120030-
/O.NEW.KMKX.TO.W.0014.210811T2334Z-210812T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Milwaukee/Sullivan WI
634 PM CDT Wed Aug 11 2021

The National Weather Service in Milwaukee/Sullivan has issued a

* Tornado Warning for...
  Southwestern Dane County in south central Wisconsin...

* Until 730 PM CDT.
    
* At 634 PM CDT, a severe thunderstorm capable of producing a tornado
  was located 7 miles north of Blanchardville, or 11 miles southwest
  of Mount Horeb, moving east at 30 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Fitchburg, Verona, Mount Horeb, Belleville, Blue Mounds, Mount
  Vernon and Paoli.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4286 8984 4301 8984 4302 8983 4304 8946
      4286 8945
TIME...MOT...LOC 2334Z 265DEG 26KT 4291 8991 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

STUMPF

1 follow-up statement

773 
WWUS53 KMKX 112349
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
649 PM CDT Wed Aug 11 2021

WIC025-112358-
/O.CAN.KMKX.TO.W.0014.000000T0000Z-210812T0030Z/
Dane WI-
649 PM CDT Wed Aug 11 2021

...THE TORNADO WARNING FOR SOUTHWESTERN DANE COUNTY IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been cancelled.  However gusty winds are
still possible with this thunderstorm.

A Tornado Watch remains in effect until 800 PM CDT for south central
Wisconsin.

LAT...LON 4286 8984 4301 8984 4302 8983 4304 8946
      4286 8945
TIME...MOT...LOC 2346Z 265DEG 26KT 4292 8976 

$$

STUMPF

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 10, 7:05 PM CDT	Special Weather Statement	MKX	Jefferson	25 min
Aug 10, 7:24 PM CDT	Severe Thunderstorm Warning	MKX	Sheboygan	51 min
Aug 10, 7:43 PM CDT	Severe Thunderstorm Warning	MKX	Kenosha, Milwaukee, Ozaukee, Racine	32 min
Aug 10, 8:07 PM CDT	Special Marine Warning	MKX		53 min
Aug 10, 8:16 PM CDT	Special Marine Warning	MKX		44 min
Aug 11, 6:44 AM CDT	Small Craft Advisory	MKX		15 hr
Aug 11, 9:58 AM CDT	Special Weather Statement	MKX	Kenosha, Milwaukee, Racine, Rock, Walworth	77 min
Aug 11, 10:06 AM CDT	Special Marine Warning	MKX		84 min
Aug 11, 2:46 PM CDT	Severe Thunderstorm Warning	MKX	Green Lake, Marquette	59 min
Aug 11, 4:22 PM CDT	Severe Thunderstorm Warning	MKX	Iowa	53 min
Aug 11, 5:05 PM CDT	Special Weather Statement	MKX	Iowa	25 min
Aug 11, 5:10 PM CDT	Severe Thunderstorm Warning	MKX	Iowa	50 min
Aug 11, 5:24 PM CDT	Special Weather Statement	MKX	Milwaukee	36 min
Aug 11, 5:49 PM CDT	Severe Thunderstorm Warning	MKX	Milwaukee, Waukesha	41 min
Aug 11, 5:56 PM CDT	Special Marine Warning	MKX		94 min
Aug 11, 5:58 PM CDT	Special Weather Statement	MKX	Iowa	47 min
Aug 11, 6:04 PM CDT	Tornado Warning	MKX	Iowa	41 min
Aug 11, 6:24 PM CDT	Severe Thunderstorm Warning	MKX	Kenosha, Racine, Walworth	53 min
Aug 11, 6:48 PM CDT	Special Marine Warning	MKX		57 min

Nearby

Tornado Warnings in Wisconsin, 2021 Every tornado warning in 2021 Tornadoes 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.