Alert archive / South Dakota / Tornado Warnings in 2007

Tornado Warning 42, NWS Sioux Falls, SD

August 21, 2007Bon Homme County, South Dakota

NWS Sioux Falls, SD issued this tornado warning at Aug 21, 2007, 6:12 PM CDT for Bon Homme County, South Dakota. It was in force for 48 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 21, 2007, 6:12 PM CDT (23:12 UTC)
Expired
Aug 21, 2007, 7:00 PM CDT
In force
48 min
Issued by
NWS Sioux Falls, SD
Area
Counties, with a storm outline in the text

County Bon Homme County, SD

The radar

The Sioux Falls radar (KFSD), 125 km from the middle of the area, began a volume at 23:13 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.

IssuedProductOfficeLasted
Aug 21, 3:45 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.2 hours before the alert went out and 218 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, Omaha, NE at 12:00Z on 2007-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 174 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, Omaha, NE at 12:00Z on 2007-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 square meters per square second.193958Sfc1 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
174 J/kg
Mixed-layer CIN
-479 J/kg
Mixed-layer LCL
1438 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
61 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 KFSD 212312
TORFSD
SDC009-220000-
/O.NEW.KFSD.TO.W.0042.070821T2312Z-070822T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
612 PM CDT TUE AUG 21 2007

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  BON HOMME COUNTY IN SOUTHEAST SOUTH DAKOTA

* UNTIL 700 PM CDT

* AT 612 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 7 MILES
  SOUTHWEST OF AVON...OR ABOUT 21 MILES SOUTHEAST OF PICKSTOWN...
  MOVING SOUTHEAST AT 30 MPH.

* THE TORNADO WILL BE NEAR...
   TYNDALL AROUND 630 PM CDT...
   SPRINGFIELD AROUND 635 PM CDT...
   TABOR AROUND 645 PM CDT...

THIS WARNING REPLACES THE SEVERE THUNDERSTORM WARNING PREVIOUSLY
ISSUED FOR THE WARNED AREA.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT TUESDAY EVENING
FOR NORTHEAST NEBRASKA.

LAT...LON 4285 9768 4287 9772 4286 9788 4278 9796
      4277 9800 4285 9816 4286 9813 4293 9810
      4294 9812 4298 9809 4304 9811 4311 9766

$$

LIEBL
2 follow-up statements
000 
WWUS53 KFSD 212330
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
629 PM CDT TUE AUG 21 2007

SDC009-220000-
/O.CON.KFSD.TO.W.0042.000000T0000Z-070822T0000Z/
BON HOMME SD-
629 PM CDT TUE AUG 21 2007

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM CDT FOR BON HOMME
COUNTY...

AT 629 PM CDT...WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS TORNADO WAS
LOCATED 8 MILES SOUTH OF AVON...OR ABOUT 27 MILES SOUTHEAST OF
PICKSTOWN...MOVING SOUTHEAST AT 25 MPH.

THE TORNADO WILL BE NEAR...
   TYNDALL AROUND 635 PM CDT...
   SPRINGFIELD AROUND 645 PM CDT...

IN ADDITION TO THE TORNADO...THIS STORM IS CAPABLE OF PRODUCING 
BASEBALL SIZE HAIL AND DESTRUCTIVE STRAIGHT LINE WINDS. 

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT TUESDAY EVENING
FOR NORTHEAST NEBRASKA.

LAT...LON 4285 9768 4287 9772 4286 9788 4278 9796
      4277 9800 4285 9816 4286 9813 4293 9810
      4294 9812 4298 9809 4311 9809 4313 9774

$$

LIEBL
000 
WWUS53 KFSD 212358
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
658 PM CDT TUE AUG 21 2007

SDC009-220008-
/O.EXP.KFSD.TO.W.0042.000000T0000Z-070822T0000Z/
BON HOMME SD-
658 PM CDT TUE AUG 21 2007

...THE TORNADO WARNING FOR BON HOMME COUNTY EXPIRES AT 700 PM CDT...
...THIS TORNADO WARNING HAS REPLACED BY A SEVERE THUNDERSTORM 
WARNING...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT TUESDAY EVENING
FOR NORTHEAST NEBRASKA. A TORNADO WATCH ALSO REMAINS IN EFFECT UNTIL
200 AM CDT WEDNESDAY MORNING FOR NORTHWEST IOWA.

LAT...LON 4285 9768 4287 9772 4286 9788 4278 9796
      4277 9800 4285 9816 4286 9813 4293 9810
      4294 9812 4298 9809 4311 9809 4313 9774

$$

LIEBL

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 3:07 AM CDTDense Fog AdvisoryFSDBrookings4 hr
Aug 21, 5:03 PM CDTSevere Thunderstorm WarningFSDCharles Mix57 min
Aug 21, 5:40 PM CDTSevere Thunderstorm WarningFSDDouglas50 min
Aug 21, 5:46 PM CDTTornado WarningFSDCharles Mix44 min
Aug 21, 5:56 PM CDTSevere Thunderstorm WarningFSDBon Homme64 min
Aug 21, 6:02 PM CDTSevere Thunderstorm WarningFSDHutchinson32 min
Aug 21, 6:36 PM CDTSevere Thunderstorm WarningFSDCharles Mix39 min
Aug 21, 6:56 PM CDTSevere Thunderstorm WarningFSDBon Homme49 min

Nearby

Tornado Warnings in South Dakota, 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.