Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 142, NWS Twin Cities, MN

December 15, 20214 counties in Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at Dec 15, 2021, 8:09 PM CST for 4 counties in Wisconsin. It was in force for 36 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: Dec 15, 2021, 8:09 PM CST (02:09 UTC)
Expired: Dec 15, 2021, 8:45 PM CST
In force: 36 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Dunn County, WI, Pepin County, WI, Pierce County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 104 km from the middle of the area, began a volume at 02:09 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
Dec 15, 5:30 PM CST	Tornado Watch	SPC	6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 2.2 hours before the alert went out and 107 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: 633 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 770 m above ground
0-6 km bulk shear: 75 kt
0-1 km storm-relative helicity: 443 m²/s²
0-3 km storm-relative helicity: 470 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 5.7

Open this sounding in Storm Lab

The text

As transmitted.

618 
WUUS53 KMPX 160209
SVRMPX
WIC033-091-093-109-160245-
/O.NEW.KMPX.SV.W.0142.211216T0209Z-211216T0245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
809 PM CST Wed Dec 15 2021

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Pepin County in west central Wisconsin...
  Pierce County in west central Wisconsin...
  Dunn County in west central Wisconsin...
  Eastern St. Croix County in west central Wisconsin...

* Until 845 PM CST.

* At 809 PM CST, severe thunderstorms were located along a line
  extending from near Prescott to near Bay City to near Pepin, moving
  northeast at 55 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Severe thunderstorms will be near...
  Pepin around 815 PM CST.
  Plum City around 820 PM CST.
  Durand and Elmwood around 825 PM CST.

Other locations in the path of these severe thunderstorms include
Baldwin, Hammond, Eau Galle, Woodville, Menomonie, Glenwood City,
Boyceville and Elk Mound.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for southeastern
and east central Minnesota...and west central Wisconsin.

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

A Tornado Watch remains in effect until 1100 PM CST for southeastern
and east central Minnesota...and west central Wisconsin.

&&

LAT...LON 4460 9200 4456 9204 4441 9209 4445 9224
      4450 9230 4456 9234 4457 9255 4461 9258
      4462 9262 4466 9264 4475 9281 4484 9277
      4519 9220 4487 9165 4460 9165
TIME...MOT...LOC 0209Z 231DEG 49KT 4478 9272 4460 9237 4441 9213 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Dye

2 follow-up statements

554 
WWUS53 KMPX 160233
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
833 PM CST Wed Dec 15 2021

WIC033-091-093-109-160245-
/O.CON.KMPX.SV.W.0142.000000T0000Z-211216T0245Z/
Pepin WI-Pierce WI-Dunn WI-St. Croix WI-
833 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 PM CST
FOR NORTHEASTERN PEPIN...NORTHEASTERN PIERCE...DUNN AND EASTERN ST.
CROIX COUNTIES...

At 832 PM CST, severe thunderstorms were located along a line
extending from Baldwin to 5 miles north of Eau Galle to 5 miles west
of Mondovi, moving east at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
  Glenwood City, Boyceville, Menomonie and Elk Mound.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for west central
Wisconsin.

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

&&

LAT...LON 4460 9200 4456 9204 4488 9271 4519 9220
      4487 9165 4460 9165
TIME...MOT...LOC 0232Z 270DEG 49KT 4495 9237 4477 9202 4458 9178 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Dye

053 
WWUS53 KMPX 160242
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
842 PM CST Wed Dec 15 2021

WIC033-091-093-109-160251-
/O.EXP.KMPX.SV.W.0142.000000T0000Z-211216T0245Z/
Pepin WI-Pierce WI-Dunn WI-St. Croix WI-
842 PM CST Wed Dec 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN PEPIN...
NORTHEASTERN PIERCE...DUNN AND EASTERN ST. CROIX COUNTIES WILL EXPIRE
AT 845 PM CST...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 1100 PM CST for west central
Wisconsin.

Remember, a Severe Thunderstorm Warning still remains in effect for
eastern Pepin and eastern Dunn Counties.

LAT...LON 4460 9200 4456 9204 4488 9271 4519 9220
      4487 9165 4460 9165
TIME...MOT...LOC 0241Z 231DEG 49KT 4500 9228 4482 9193 4463 9169 

$$

Dye

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 15, 8:17 PM CST	Tornado Warning	MPX	Dunn, Pepin	28 min
Dec 15, 8:31 PM CST	Severe Thunderstorm Warning	MPX	Chippewa, Dunn, Eau Claire, Pepin	44 min
Dec 15, 9:10 PM CST	Severe Thunderstorm Warning	MPX	Chippewa, Rusk	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.