Alert archive / South Dakota / Tornado Warnings in 2011

Tornado Warning 12, NWS Aberdeen, SD

July 8, 2011McPherson County, South Dakota

NWS Aberdeen, SD issued this tornado warning at Jul 8, 2011, 11:08 PM CDT for McPherson County, South Dakota. It was in force for 37 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: Jul 8, 2011, 11:08 PM CDT (04:08 UTC)
Expired: Jul 8, 2011, 11:45 PM CDT
In force: 37 min
Issued by: NWS Aberdeen, SD
Area: Storm-based polygon

County McPherson County, SD

The radar

The Aberdeen radar (KABR), 68 km from the middle of the area, began a volume at 04:08 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

Aberdeen, SD (KABR), launched 00:00Z, 4.1 hours before the alert went out and 120 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: 975 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 1645 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 48 m²/s²
0-3 km storm-relative helicity: 117 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 4.2

Open this sounding in Storm Lab

The text

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

910 
WFUS53 KABR 090408
TORABR
SDC089-090445-
/O.NEW.KABR.TO.W.0012.110709T0408Z-110709T0445Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ABERDEEN SD
1108 PM CDT FRI JUL 8 2011

THE NATIONAL WEATHER SERVICE IN ABERDEEN HAS ISSUED A

* TORNADO WARNING FOR...
  NORTH CENTRAL MCPHERSON COUNTY IN NORTH CENTRAL SOUTH DAKOTA...

* UNTIL 1145 PM CDT

* AT 1106 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR LONG LAKE...OR 23 MILES EAST OF EUREKA...AND
  MOVING EAST AT 30 MPH.

* THIS TORNADIC STORM WILL BE NEAR...
  SPRING CREEK COLONY AROUND 1135 PM CDT...

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.

TORNADOES ARE DIFFICULT TO SEE AND CONFIRM AT NIGHT. TAKE COVER NOW.

&&

LAT...LON 4593 9882 4576 9890 4579 9931 4595 9927
      4595 9907
TIME...MOT...LOC 0408Z 279DEG 26KT 4587 9916

$$
WISE

1 follow-up statement

927 
WWUS53 KABR 090439
SVSABR

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
1139 PM CDT FRI JUL 8 2011

SDC089-090449-
/O.EXP.KABR.TO.W.0012.000000T0000Z-110709T0445Z/
MCPHERSON SD-
1139 PM CDT FRI JUL 8 2011

...THE TORNADO WARNING FOR NORTH CENTRAL MCPHERSON COUNTY WILL EXPIRE
AT 1145 PM CDT/1045 PM MDT/...

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

LAT...LON 4593 9882 4576 9890 4579 9931 4595 9927
      4595 9907
TIME...MOT...LOC 0439Z 279DEG 26KT 4583 9884

$$
CONNELLY

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 8, 10:29 PM CDT	Severe Thunderstorm Warning	ABR	Jones, Lyman, Stanley	31 min
Jul 8, 10:49 PM CDT	Severe Thunderstorm Warning	ABR	Hughes, Stanley, Sully	26 min
Jul 8, 10:54 PM CDT	Severe Thunderstorm Warning	ABR	Brown, McPherson	51 min
Jul 8, 11:24 PM CDT	Severe Thunderstorm Warning	ABR	Jones, Lyman, Stanley	35 min
Jul 8, 11:26 PM CDT	Tornado Warning	ABR	Brown, McPherson	34 min
Jul 8, 11:35 PM CDT	Severe Thunderstorm Warning	ABR	Brown, McPherson, Marshall	40 min

Nearby

Tornado Warnings in South Dakota, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.