Alert archive / Wisconsin / Tornado Warnings in 2011

Tornado Warning 3, NWS Twin Cities, MN

April 10, 2011Eau Claire County, Wisconsin

NWS Twin Cities, MN issued this tornado warning at Apr 10, 2011, 4:52 PM CDT for Eau Claire County, Wisconsin. It was in force for 23 min. 7 reports 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: Apr 10, 2011, 4:52 PM CDT (21:52 UTC)
Expired: Apr 10, 2011, 5:15 PM CDT
In force: 23 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon

County Eau Claire County, WI

The radar

The La Crosse radar (KARX), 93 km from the middle of the area, began a volume at 21:56 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
Apr 10, 5:00 PM CDT	TSTM WND DMG	5 Ssw Augusta, WI	ROOFS OFF 2 MOBILE HOMES. DAMAGE SURVEY TO BE DONE ON MONDAY.
Apr 10, 5:00 PM CDT	TORNADO 1	5 Sw Augusta, WI	EF1 TORNADO WITH MAXIMUM WIND SPEED OF 95 TO 105 MPH. PATH LENGTH APPROX 1.5 MILES...PATH WIDTH APPROX 200 YARDS...ON THE GROUND FOR APPROX 2 MINUTES. 2 FARMSTEADS WERE DIRECTLY IMPACTED WITH SEVERE TREE DAMAGE INCLUDING UPROOTED TREES AND A GARAGE THAT WAS CO
Apr 10, 5:00 PM CDT	TORNADO	N Augusta, WI	TREES DOWN...BARN DAMAGE...AND SNAPPED POWER POLES ON THE NORTH SIDE OF AUGUSTA.
Apr 10, 5:05 PM CDT	TSTM WND GST 78	1 Nnw Augusta, WI	MEASURED AT RAWS SITE.
Apr 10, 5:05 PM CDT	TORNADO 1	1 Nw Augusta, WI	EF1 TORNADO WITH MAXIMUM WIND SPEEDS OF 90 TO 100 MPH. PATH LENGTH APPROX THREE QUARTERS OF A MILE...PATH WIDTH APPROX 150 YARDS...ON THE GROUND FOR APPROX 1 MINUTE. TREES DOWN...SEVERAL STRUCTURES DAMAGED...AND SNAPPED POWER POLES.
Apr 10, 5:09 PM CDT	TSTM WND GST 60	Augusta, WI	ESTIMATED FROM SHERIFF.
Apr 10, 5:09 PM CDT	HAIL 1	Augusta, WI

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 10, 3:19 PM CDT	Tornado Watch PDS	SPC	7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 9.9 hours before the alert went out and 190 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: 552 J/kg
Mixed-layer CIN: -270 J/kg
Mixed-layer LCL: 643 m above ground
0-6 km bulk shear: 80 kt
0-1 km storm-relative helicity: 528 m²/s²
0-3 km storm-relative helicity: 499 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

020 
WFUS53 KMPX 102152
TORMPX
WIC035-102215-
/O.NEW.KMPX.TO.W.0003.110410T2152Z-110410T2215Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
452 PM CDT SUN APR 10 2011

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEASTERN EAU CLAIRE COUNTY IN WEST CENTRAL WISCONSIN...

* UNTIL 515 PM CDT

* AT 449 PM CDT...RADAR INDICATED A STORM CAPABLE OF PRODUCING A
  TORNADO. THE MOST DANGEROUS PART OF THE STORM WAS 8 MILES SOUTHWEST
  OF ALLEN...OR ABOUT 3 MILES WEST OF STRUM...AND MOVING NORTHEAST AT
  60 MPH.

* LOCATIONS IN THE WARNING INCLUDE...
  FOSTER...
  FAIRCHILD...
  ALLEN...
  AUGUSTA...
  INTERSTATE 94...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

WHEN A TORNADO WARNING IS ISSUED BASED ON RADAR...IT MEANS THAT
STRONG ROTATION HAS BEEN DETECTED IN THE STORM. A TORNADO MAY ALREADY
BE ON THE GROUND...OR IS EXPECTED TO DEVELOP SHORTLY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1100 PM CDT SUNDAY EVENING
FOR NORTHWESTERN WISCONSIN.

&&

LAT...LON 4459 9138 4458 9144 4464 9153 4484 9092
      4481 9091 4459 9092
TIME...MOT...LOC 2152Z 246DEG 53KT 4458 9140

$$

1 follow-up statement

593 
WWUS53 KMPX 102202
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
502 PM CDT SUN APR 10 2011

WIC035-102215-
/O.CON.KMPX.TO.W.0003.000000T0000Z-110410T2215Z/
EAU CLAIRE WI-
502 PM CDT SUN APR 10 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHEASTERN EAU CLAIRE
COUNTY IN WEST CENTRAL WISCONSIN UNTIL 515 PM CDT...

AT 458 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS STORM
WAS LOCATED NEAR FOSTER...OR 17 MILES NORTH OF WHITEHALL...MOVING 
NORTHEAST AT 60 MPH. TRAINED STORM SPOTTERS REPORTED A WALL CLOUD 
WITH THIS STORM WEST OF FOSTER.

LOCATIONS IMPACTED INCLUDE...
  FAIRCHILD AND AUGUSTA AND INTERSTATE 94.

LAT...LON 4459 9092 4459 9132 4469 9137 4478 9110
      4484 9092
TIME...MOT...LOC 2202Z 246DEG 53KT 4464 9121

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 10, 3:20 PM CDT	Special Weather Statement	MPX	Dunn, Pierce	25 min
Apr 10, 3:34 PM CDT	Severe Thunderstorm Warning	MPX	Barron, Chippewa, Dunn, Pierce, Saint Croix	41 min
Apr 10, 4:07 PM CDT	Special Weather Statement	MPX	Pepin	23 min
Apr 10, 4:09 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Dunn, Eau Claire, Pepin	51 min
Apr 10, 4:19 PM CDT	Special Weather Statement	MPX	Pierce	41 min
Apr 10, 4:19 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Eau Claire, Pepin	41 min
Apr 10, 4:32 PM CDT	Severe Thunderstorm Warning	MPX	Barron, Chippewa, Dunn, Rusk	43 min
Apr 10, 4:41 PM CDT	Tornado Warning	MPX	Chippewa, Eau Claire	49 min
Apr 10, 4:43 PM CDT	Tornado Warning	MPX	Barron, Chippewa, Dunn, Rusk	37 min
Apr 10, 5:00 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Dunn, Rusk	28 min
Apr 10, 5:14 PM CDT	Tornado Warning	MPX	Eau Claire	16 min

Nearby

Tornado Warnings in Wisconsin, 2011 Every tornado warning in 2011 Tornadoes in 2011

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.