Alert archive / South Dakota / Tornado Warnings in 2021

Tornado Warning 18, NWS Aberdeen, SD

October 9, 2021Roberts County, South Dakota

NWS Aberdeen, SD issued this tornado warning at Oct 9, 2021, 6:28 PM CDT for Roberts County, South Dakota. It was in force for 21 min. 1 report 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
Oct 9, 2021, 6:28 PM CDT (23:28 UTC)
Expired
Oct 9, 2021, 6:49 PM CDT
In force
21 min
Issued by
NWS Aberdeen, SD
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Roberts County, SD

The radar

The Aberdeen radar (KABR), 119 km from the middle of the area, began a volume at 23:29 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
Oct 9, 6:36 PM CDTTSTM WND DMG3 Nw Peever, SD30 FOOT TRAILER PULLED BY A PICK UP TRUCK OVERTURNED ON INTERSTATE 29. TIME ESTIMATED BY RADAR.

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
Oct 9, 2:56 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 11.5 hours before the alert went out and 138 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 12:00Z on 2021-10-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4 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, Aberdeen, SD at 12:00Z on 2021-10-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 97 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
4 J/kg
Mixed-layer CIN
-89 J/kg
Mixed-layer LCL
713 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
97 m²/s²
0-3 km storm-relative helicity
200 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

362 
WFUS53 KABR 092328
TORABR
SDC109-100000-
/O.NEW.KABR.TO.W.0018.211009T2328Z-211010T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Aberdeen SD
628 PM CDT Sat Oct 9 2021

The National Weather Service in Aberdeen has issued a

* Tornado Warning for...
  Southwestern Roberts County in northeastern South Dakota...

* Until 700 PM CDT.
    
* At 628 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Finley Heights Housing, or 15 miles south of
  Sisseton, moving northeast at 30 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Agency Village around 640 PM CDT.
  Peever and Peever Flats Housing around 645 PM CDT.

Other locations in the path of this tornadic thunderstorm include
Browns Valley and Dakota Connection & Casino.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4564 9684 4560 9685 4554 9678 4551 9676
      4534 9697 4545 9716 4567 9697
TIME...MOT...LOC 2328Z 216DEG 27KT 4543 9703 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Connelly
1 follow-up statement
413 
WWUS53 KABR 092349
SVSABR

Severe Weather Statement
National Weather Service Aberdeen SD
649 PM CDT Sat Oct 9 2021

SDC109-092359-
/O.CAN.KABR.TO.W.0018.000000T0000Z-211010T0000Z/
Roberts SD-
649 PM CDT Sat Oct 9 2021

...THE TORNADO WARNING FOR SOUTHWESTERN ROBERTS COUNTY IS
CANCELLED...
    
The tornado threat has diminished and the Tornado Warning has been
cancelled. However, large hail and damaging winds remain likely and a
Severe Thunderstorm Warning remains in effect for the area.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
west central Minnesota...and northeastern South Dakota.

LAT...LON 4564 9684 4560 9685 4554 9678 4551 9676
      4534 9697 4545 9716 4567 9697
TIME...MOT...LOC 2346Z 216DEG 27KT 4556 9690 

$$

Connelly

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 9, 12:05 PM CDTSevere Thunderstorm WarningABRJones, Lyman27 min
Oct 9, 1:57 PM CDTSpecial Weather StatementABRLyman33 min
Oct 9, 4:10 PM CDTTornado WarningABRBrown, Spink35 min
Oct 9, 4:30 PM CDTTornado WarningABRBrown15 min
Oct 9, 4:33 PM CDTSevere Thunderstorm WarningABRBrown, Clark, Codington, Day, Hamlin, Spink42 min
Oct 9, 4:33 PM CDTTornado Warning Tornado observedABRBrown, Day, Spink27 min
Oct 9, 4:57 PM CDTTornado WarningABRBrown, Day, Marshall18 min
Oct 9, 5:16 PM CDTTornado WarningABRDay, Marshall29 min
Oct 9, 5:17 PM CDTTornado WarningABRBrown, Day, Marshall28 min
Oct 9, 5:18 PM CDTSevere Thunderstorm WarningABRBrown, Clark, Codington, Day, Grant, Hamlin and 2 more57 min
Oct 9, 5:44 PM CDTTornado WarningABRBrown, Marshall31 min
Oct 9, 5:47 PM CDTTornado WarningABRDay, Marshall, Roberts28 min
Oct 9, 6:07 PM CDTTornado Warning Tornado observedABRDay, Roberts23 min
Oct 9, 6:14 PM CDTTornado WarningABRMarshall, Roberts31 min
Oct 9, 6:15 PM CDTSevere Thunderstorm WarningABRCodington, Day, Deuel, Grant, Hamlin, Marshall and 1 more60 min

Nearby

Tornado Warnings in South Dakota, 2021Every tornado warning in 2021Tornadoes in 2021

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.