Alert archive / Wisconsin / Tornado Warnings in 2007

Tornado Warning 27, NWS Twin Cities, MN

September 18, 2007Saint Croix County, Wisconsin

NWS Twin Cities, MN issued this tornado warning at Sep 18, 2007, 6:45 PM CDT for Saint Croix County, Wisconsin. It was in force for 33 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
Sep 18, 2007, 6:45 PM CDT (23:45 UTC)
Expired
Sep 18, 2007, 7:18 PM CDT
In force
33 min
Issued by
NWS Twin Cities, MN
Area
Counties, with a storm outline in the text

County Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 90 km from the middle of the area, began a volume at 23:47 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 nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.8 hours before the alert went out and 93 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 12:00Z on 2007-09-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 327 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 12:00Z on 2007-09-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 92 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
327 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
618 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
92 m²/s²
0-3 km storm-relative helicity
100 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KMPX 182345
TORMPX
WIC109-190030-
/O.NEW.KMPX.TO.W.0027.070918T2345Z-070919T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
645 PM CDT TUE SEP 18 2007

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

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

* UNTIL 730 PM CDT

* AT 642 PM CDT...RADAR INDICATED A STORM CAPABLE OF PRODUCING A
  TORNADO. THE MOST DANGEROUS PART OF THE STORM WAS 6 MILES SOUTH OF
  ROBERTS...OR ABOUT 10 MILES SOUTHEAST OF HUDSON...AND MOVING
  NORTHEAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  ROBERTS...
  HAMMOND...
  BALDWIN...
  WOODVILLE...
  HERSEY...
  WILSON...
  EMERALD...
  FOREST...

WHEN A TORNADO WARNING IS ISSUED BASED ON DOPPLER 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.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
STURDY SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE NEAREST
DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

LAT...LON 4502 9259 4519 9217 4486 9216 4487 9270
TIME...MOT...LOC 2345Z 229DEG 32KT 4491 9254

$$

MB
2 follow-up statements
000 
WWUS53 KMPX 190002
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
700 PM CDT TUE SEP 18 2007

WIC109-190030-
/O.CON.KMPX.TO.W.0027.000000T0000Z-070919T0030Z/
ST. CROIX WI-
700 PM CDT TUE SEP 18 2007

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 PM CDT FOR ST. CROIX
COUNTY...

AT 655 PM CDT...DOPPLER RADAR CONTINUED TO INDICATE A SEVERE 
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THE SEVERE THUNDERSTORM 
WAS LOCATED 3 MILES WEST OF HAMMOND...OR ABOUT 12 MILES EAST OF 
HUDSON...AND MOVING NORTHEAST AT 25 MPH. AT 650 PM CDT... A TRAINED 
SPOTTER REPORTED A WALL CLOUD 4 TO 5 MILES SOUTH OF ROBERTS.

OTHER LOCATIONS IN THE WARNING INCLUDE HERSEY...FOREST...EMERALD...
WOODVILLE...WILSON...ROBERTS...HAMMOND...GLENWOOD CITY AND BALDWIN.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

LAT...LON 4502 9259 4519 9217 4486 9216 4487 9270
TIME...MOT...LOC 0000Z 227DEG 25KT 4498 9245

$$

MB
000 
WWUS53 KMPX 190018
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
718 PM CDT TUE SEP 18 2007

WIC109-190028-
/O.CAN.KMPX.TO.W.0027.000000T0000Z-070919T0030Z/
ST. CROIX WI-
718 PM CDT TUE SEP 18 2007

...THE TORNADO WARNING FOR ST. CROIX COUNTY IS CANCELLED...

THE STORM HAS WEAKENED...AND NO LONGER APPEARS TORNADIC. THEREFORE...
THE TORNADO WARNING HAS BEEN CANCELLED.

LAT...LON 4502 9259 4519 9217 4486 9216 4487 9270
TIME...MOT...LOC 0018Z 227DEG 25KT 4506 9231

$$

MB

Nearby

Tornado Warnings in Wisconsin, 2007Every tornado warning in 2007Tornadoes in 2007

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.