Alert archive / Wisconsin / Tornado Warnings in 2009

Tornado Warning 32, NWS Twin Cities, MN

August 8, 2009Saint Croix County, Wisconsin; Washington County, Minnesota

NWS Twin Cities, MN issued this tornado warning at Aug 8, 2009, 10:01 PM CDT for Saint Croix County, Wisconsin; Washington County, Minnesota. It was in force for 29 min. 4 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
Aug 8, 2009, 10:01 PM CDT (03:01 UTC)
Expired
Aug 8, 2009, 10:30 PM CDT
In force
29 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon

Counties Washington County, MN, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 71 km from the middle of the area, began a volume at 03:02 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.

What was reported inside it

TimeReportWhereRemark
Aug 8, 10:20 PM CDTTSTM WND DMG2 N Burkhardt, WINUMEROUS POWER LINES AND TREES TOPPLED IN ST JOSEPH TOWNSHIP NEAR OAKWOOD LANE. HOME OWNER AT 1223 OAKWOOD LANE REPORTED GARAGE RIPPED APART AND BOAT SUCKED AWAY.
Aug 8, 10:25 PM CDTTSTM WND DMG1 N Burkhardt, WIMAJOR DAMAGE TO 4 HOMES. LOTS OF TREES DOWN. TIME OF EVENT ESTIMATED. DAMAGE SURVEY PLANNED AROUND BOARDMAN AND BURKHARDT.
Aug 8, 10:25 PM CDTTORNADO1 Nnw Burkhardt, WIDAMAGE SURVEY DETERMINED AN EF-1 TORNADO TOUCHED DOWN AND TRAVELLED FIVE MILES TO TWO MILES SOUTHEAST OF BOARDMAN. NUMEROUS TREES WERE SNAPPED. SEVERAL GARAGES AND A BOAT WERE BLOWN AWAY. TORNADO WAS ACCOMPANIED BY VERY STRONG SOUTHERLY INFLOW WINDS THAT ALSO
Aug 8, 10:40 PM CDTTSTM WND DMG2 N Burkhardt, WINUMEROUS POWER LINES AND TREES TOPPLED IN ST JOSEPH TOWNSHIP NEAR OAKWOOD LANE. HOME OWNER AT 1223 OAKWOOD LANE REPORTED GARAGE RIPPED APART AND BOAT SUCKED AWAY.

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.

IssuedProductOfficeLasted
Aug 8, 3:46 PM CDTTornado WatchSPC8 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 3.0 hours before the alert went out and 74 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-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2009-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3715 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2009-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 190 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
3715 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
841 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
190 m²/s²
0-3 km storm-relative helicity
163 m²/s²
Significant tornado parameter
3.8
Supercell composite
16.8

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KMPX 090301
TORMPX
MNC163-WIC109-090330-
/O.NEW.KMPX.TO.W.0032.090809T0301Z-090809T0330Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1001 PM CDT SAT AUG 8 2009

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL WASHINGTON COUNTY IN EAST CENTRAL MINNESOTA...
  WEST CENTRAL ST. CROIX COUNTY IN WEST CENTRAL WISCONSIN...

* UNTIL 1030 PM CDT

* AT 1000 PM CDT...RADAR INDICATED A STORM CAPABLE OF PRODUCING A
  TORNADO. THE MOST DANGEROUS PART OF THE STORM WAS FIVE MILES
  WEST OF STILLWATER...AND MOVING EAST AT 20 MPH...TOWARD
  STILLWATER.

* LOCATIONS IN THE WARNING INCLUDE...
  STILLWATER...
  BAYPORT...
  BURKHARDT...
  OAK PARK HEIGHTS...
  NORTH HUDSON...

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 MIDNIGHT CDT SUNDAY MORNING
FOR EAST CENTRAL MINNESOTA AND NORTHWESTERN WISCONSIN.

&&

LAT...LON 4506 9257 4497 9256 4501 9289 4508 9290
TIME...MOT...LOC 0301Z 272DEG 18KT 4505 9285

$$
1 follow-up statement
000 
WWUS53 KMPX 090320
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1020 PM CDT SAT AUG 8 2009

MNC163-090328-
/O.CAN.KMPX.TO.W.0032.000000T0000Z-090809T0330Z/
WASHINGTON MN-
1020 PM CDT SAT AUG 8 2009

...THE TORNADO WARNING FOR CENTRAL WASHINGTON COUNTY IS CANCELLED...

RADAR INDICATED THAT THE SEVERE STORM HAD WEAKENED OR MOVED OUT OF 
THE WARNED AREA. THEREFORE...THE TORNADO WARNING HAS BEEN CANCELLED 
FOR THE STILLWATER AND BAYPORT AREAS. THE OTHER TORNADO WARNING 
CONTINUES FOR NORTHEASTERN WASHINGTON COUNTY AND MARINE ON ST CROIX.


LAT...LON 4500 9276 4507 9277 4506 9257 4497 9256
TIME...MOT...LOC 0318Z 272DEG 18KT 4504 9271

$$

WIC109-090330-
/O.CON.KMPX.TO.W.0032.000000T0000Z-090809T0330Z/
ST. CROIX WI-
1020 PM CDT SAT AUG 8 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1030 PM CDT FOR WEST
CENTRAL ST. CROIX COUNTY...

AT 1017 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM WITH STRONG
ROTATION.  THE MOST DANGEROUS PART OF THE STORM WAS LOCATED 3 MILES 
WEST OF BURKHARDT...AND MOVING EAST AT 20 MPH. A FUNNEL CLOUD WAS 
SPOTTED AT 1010 PM WITH THIS STORM.

LOCATIONS IN THE WARNING INCLUDE...
BURKHARDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM HAS A HISTORY OR PRODUCING TORNADOES AND LARGE DAMAGING
HAIL.

&&

LAT...LON 4500 9276 4507 9277 4506 9257 4497 9256
TIME...MOT...LOC 0318Z 272DEG 18KT 4504 9271

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 8, 9:43 PM CDTTornado WarningMPXPolk, Saint Croix32 min
Aug 8, 10:14 PM CDTTornado WarningMPXPolk, Saint Croix31 min
Aug 8, 10:29 PM CDTTornado WarningMPXSaint Croix46 min
Aug 8, 11:14 PM CDTTornado WarningMPXDunn, Saint Croix46 min
Aug 9, 12:00 AM CDTTornado WarningMPXDunn30 min
Aug 9, 12:36 AM CDTSpecial Weather StatementMPXChippewa, Eau Claire54 min
Aug 9, 1:27 AM CDTSpecial Weather StatementMPXChippewa33 min
Aug 8, 8:31 PM CDTTornado WarningMPXHennepin29 min
Aug 8, 8:49 PM CDTTornado WarningMPXAnoka, Hennepin, Ramsey26 min
Aug 8, 9:13 PM CDTTornado WarningMPXAnoka, Ramsey, Washington32 min

Nearby

Tornado Warnings in Wisconsin, 2009Tornado Warnings in Minnesota, 2009Every tornado warning in 2009Tornadoes in 2009

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.