Alert archive / South Dakota / Tornado Warnings in 2013

Tornado Warning 19, NWS Sioux Falls, SD

October 4, 2013Union County, South Dakota; Plymouth County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Oct 4, 2013, 6:57 PM CDT for Union County, South Dakota; Plymouth County, Iowa. It was in force for 18 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: Oct 4, 2013, 6:57 PM CDT (23:57 UTC)
Expired: Oct 4, 2013, 7:15 PM CDT
In force: 18 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.25 in

Counties Plymouth County, IA, Union County, SD

The radar

The Sioux Falls radar (KFSD), 112 km from the middle of the area, began a volume at 23:58 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
Oct 4, 2:38 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 12.0 hours before the alert went out and 141 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: 97 J/kg
Mixed-layer CIN: -211 J/kg
Mixed-layer LCL: 898 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 76 m²/s²
0-3 km storm-relative helicity: 128 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.9

Open this sounding in Storm Lab

The text

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

561 
WFUS53 KFSD 042357
TORFSD
IAC149-SDC127-050015-
/O.NEW.KFSD.TO.W.0019.131004T2357Z-131005T0015Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
657 PM CDT FRI OCT 4 2013

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN PLYMOUTH COUNTY IN NORTHWEST IOWA...
  SOUTHEASTERN UNION COUNTY IN SOUTHEAST SOUTH DAKOTA...

* UNTIL 715 PM CDT

* AT 654 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED NEAR JEFFERSON...AND MOVING NORTHEAST AT 45
  MPH.

  HAZARD...TORNADO AND HALF DOLLAR SIZE HAIL.

  SOURCE...RADAR INDICATED ROTATION.

  IMPACT...MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE TO
           ROOFS...WINDOWS AND VEHICLES WILL OCCUR. FLYING DEBRIS
           WILL BE DEADLY TO PEOPLE AND ANIMALS. TREE DAMAGE IS
           LIKELY.

* THIS DANGEROUS STORM WILL AFFECT MAINLY RURAL AREAS OF SOUTHEASTERN
  UNION AND SOUTHWESTERN PLYMOUTH COUNTIES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4260 9670 4276 9661 4260 9640 4256 9647
      4256 9649 4255 9648 4252 9655 4251 9658
TIME...MOT...LOC 2357Z 216DEG 37KT 4258 9656

TORNADO...RADAR INDICATED
HAIL...1.25IN

$$

CHAPMAN

1 follow-up statement

973 
WWUS53 KFSD 050010
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
710 PM CDT FRI OCT 4 2013

IAC149-SDC127-050020-
/O.EXP.KFSD.TO.W.0019.000000T0000Z-131005T0015Z/
PLYMOUTH IA-UNION SD-
710 PM CDT FRI OCT 4 2013

...THE TORNADO WARNING FOR SOUTHEASTERN UNION AND SOUTHWESTERN
PLYMOUTH COUNTIES WILL EXPIRE AT 715 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED AND MOVED OUT OF
THE WARNED AREA.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 10 PM CDT.

LAT...LON 4260 9670 4276 9661 4260 9640 4256 9647
      4256 9649 4255 9648 4252 9655 4251 9658
TIME...MOT...LOC 0010Z 216DEG 37KT 4269 9645

$$

CHAPMAN

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 4, 6:11 PM CDT	Tornado Warning Tornado observed	FSD	Union	49 min
Oct 4, 6:07 PM CDT	Tornado Warning	FSD	Woodbury	38 min
Oct 4, 6:43 PM CDT	Tornado Warning	FSD	Cherokee, Ida, Plymouth, Woodbury	47 min
Oct 4, 6:55 PM CDT	Tornado Warning Tornado observed	FSD	Plymouth, Sioux	50 min

Nearby

Tornado Warnings in South Dakota, 2013 Tornado Warnings in Iowa, 2013 Every tornado warning in 2013 Tornadoes in 2013

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.