Alert archive / South Dakota / Tornado Warnings in 2011

Tornado Warning 21, NWS Aberdeen, SD

July 26, 2011Marshall County, Roberts County, South Dakota

NWS Aberdeen, SD issued this tornado warning at Jul 26, 2011, 8:36 PM CDT for Marshall County, Roberts County, South Dakota. It was in force for 24 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
Jul 26, 2011, 8:36 PM CDT (01:36 UTC)
Expired
Jul 26, 2011, 9:00 PM CDT
In force
24 min
Issued by
NWS Aberdeen, SD
Area
Storm-based polygon

Counties Marshall County, SD, Roberts County, SD

The radar

The Aberdeen radar (KABR), 85 km from the middle of the area, began a volume at 01:40 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
Jul 26, 8:40 PM CDTTORNADO7 Se Britton, SDNWS STORM SURVEY CONFIRMED AN EF-0 TORNADO 7 MILES SOUTHEAST OF BRITTON. CONVERGENT TREE DAMAGE WAS NOTED IN THIS AREA. NO DAMAGE TO STURCTURES OR HOMES.
Jul 26, 8:45 PM CDTTSTM WND DMG4 Ssw Lake City, SD20 YEAR OLD TREE BROKEN, MEASURED 3.40 INCHES OF RAIN, PICTURE WINDOW MOVED IN AND OUT, 2 FUNNEL CLOUDS SPOTTED
Jul 26, 9:00 PM CDTTSTM WND DMG6 Ese Britton, SD4 EVERGREENS UPROOTED...SEVERAL BRANCHES DOWN. NEIGHBORS HAVE LOST 1 SHED...ANOTHER HAS BEEN DAMAGED.
Jul 26, 9:00 PM CDTTSTM WND DMG6 Nw Fort Sisseton Stat, SDSEVERAL TREES DOWN...HAY BALES MOVED...SHINGLE DAMAGE TO HOME

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
Jul 26, 7:32 PM CDTTornado WatchSPC5 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 1.6 hours before the alert went out and 114 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, Aberdeen, SD at 00:00Z on 2011-07-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3555 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Aberdeen, SD at 00:00Z on 2011-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 289 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
3555 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
900 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
289 m²/s²
0-3 km storm-relative helicity
399 m²/s²
Significant tornado parameter
7.2
Supercell composite
32.6

Open this sounding in Storm Lab

The text

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

323 
WFUS53 KABR 270136
TORABR
SDC091-109-270200-
/O.NEW.KABR.TO.W.0021.110727T0136Z-110727T0200Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ABERDEEN SD
836 PM CDT TUE JUL 26 2011

THE NATIONAL WEATHER SERVICE IN ABERDEEN HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEASTERN MARSHALL COUNTY IN NORTHEAST SOUTH DAKOTA...
  WEST CENTRAL ROBERTS COUNTY IN NORTHEAST SOUTH DAKOTA...

* UNTIL 900 PM CDT

* AT 835 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR FORT SISSETON STATE PARK...OR 10 MILES
  SOUTHEAST OF BRITTON...AND MOVING EAST AT 40 MPH.

* THIS TORNADIC STORM WILL BE NEAR...
  ROY LAKE STATE PARK AND LAKE CITY AROUND 845 PM CDT...
  EDEN AROUND 850 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.

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR
THE TORNADO. TAKE COVER NOW.

&&

LAT...LON 4571 9716 4554 9719 4554 9722 4556 9723
      4556 9732 4557 9737 4558 9737 4558 9745
      4563 9772 4579 9766
TIME...MOT...LOC 0137Z 278DEG 33KT 4572 9755

$$
HINTZ
2 follow-up statements
781 
WWUS53 KABR 270148
SVSABR

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
848 PM CDT TUE JUL 26 2011

SDC091-109-270200-
/O.CON.KABR.TO.W.0021.000000T0000Z-110727T0200Z/
ROBERTS SD-MARSHALL SD-
848 PM CDT TUE JUL 26 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHEASTERN MARSHALL AND
WEST CENTRAL ROBERTS COUNTIES UNTIL 900 PM CDT...

AT 844 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED NEAR ROY LAKE STATE PARK...OR 15 MILES EAST OF
BRITTON...MOVING EAST AT 40 MPH.

THIS TORNADO WILL AFFECT MAINLY RURAL AREAS OF SOUTHEASTERN MARSHALL
AND WEST CENTRAL ROBERTS 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.

HEAVY RAINFALL MAY HIDE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR THE
TORNADO. TAKE COVER NOW.

&&

A TORNADO WATCH REMAINS IN EFFECT UNTIL 300 AM CDT WEDNESDAY MORNING
FOR WEST CENTRAL MINNESOTA AND NORTHEAST SOUTH DAKOTA. A TORNADO
WATCH ALSO REMAINS IN EFFECT UNTIL 100 AM CDT WEDNESDAY MORNING FOR
NORTHEASTERN SOUTH DAKOTA.

LAT...LON 4571 9716 4554 9719 4554 9722 4556 9723
      4556 9732 4557 9737 4558 9737 4559 9742
      4562 9764 4578 9758
TIME...MOT...LOC 0148Z 278DEG 33KT 4570 9741

$$
HINTZ
822 
WWUS53 KABR 270156 RRA
SVSABR

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
856 PM CDT TUE JUL 26 2011

SDC091-109-270207-
/O.EXP.KABR.TO.W.0021.000000T0000Z-110727T0200Z/
ROBERTS SD-MARSHALL SD-
856 PM CDT TUE JUL 26 2011

...THE TORNADO WARNING FOR SOUTHEASTERN MARSHALL AND WEST CENTRAL 
ROBERTS COUNTIES WILL EXPIRE AT 900 PM CDT...

THE TORNADO THREAT HAS DIMINISHED...THEREFORE THE TORNADO WARNING HAS
EXPIRED. HOWEVER...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT
FOR THE AREA.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 300 AM CDT WEDNESDAY MORNING
FOR WEST CENTRAL MINNESOTA AND NORTHEAST SOUTH DAKOTA. A TORNADO
WATCH ALSO REMAINS IN EFFECT UNTIL 100 AM CDT WEDNESDAY MORNING FOR
NORTHEASTERN SOUTH DAKOTA.

LAT...LON 4571 9716 4554 9719 4554 9722 4556 9723
      4556 9732 4557 9737 4558 9737 4559 9742
      4562 9764 4578 9758
TIME...MOT...LOC 0157Z 278DEG 33KT 4569 9729

$$
HINTZ

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 26, 7:03 PM CDTTornado WarningABREdmunds, Potter, Walworth27 min
Jul 26, 7:24 PM CDTTornado WarningABREdmunds, Walworth36 min
Jul 26, 7:28 PM CDTSevere Thunderstorm WarningABRBuffalo, Faulk, Hand, Hyde, Lyman, Spink47 min
Jul 26, 7:34 PM CDTSevere Thunderstorm WarningABRBrown, Marshall56 min
Jul 26, 7:54 PM CDTSevere Thunderstorm WarningABRBrown, Edmunds, Marshall66 min
Jul 26, 8:25 PM CDTSevere Thunderstorm WarningABRDay, Marshall, Roberts65 min
Jul 26, 8:30 PM CDTTornado WarningABRMarshall, Roberts30 min
Jul 26, 8:42 PM CDTSevere Thunderstorm WarningABRDay, Marshall, Roberts48 min
Jul 26, 9:04 PM CDTSevere Thunderstorm WarningABRBrown, Day, Marshall41 min
Jul 26, 9:11 PM CDTFlash Flood WarningABRBrown, Marshall, Roberts6 hr
Jul 26, 9:11 PM CDTSevere Thunderstorm WarningABRClark, Hamlin, Spink49 min
Jul 26, 9:20 PM CDTSevere Thunderstorm WarningABRDay, Grant, Marshall, Roberts40 min
Jul 26, 9:42 PM CDTSevere Thunderstorm WarningABRDay, Marshall33 min
Jul 26, 9:56 PM CDTSevere Thunderstorm WarningABRDay, Grant, Roberts64 min
Jul 27, 12:44 PM CDTAreal Flood WarningABRMarshall7 days
Jul 27, 2:13 PM CDTAreal Flood WarningABRRoberts72 hr

Nearby

Tornado Warnings in South Dakota, 2011Every tornado warning in 2011Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.