Alert archive / South Dakota / Tornado Warnings in 2021

Tornado Warning 17, NWS Aberdeen, SD

October 9, 2021Marshall County, Roberts County, South Dakota

NWS Aberdeen, SD issued this tornado warning at Oct 9, 2021, 6:14 PM CDT for Marshall County, Roberts County, South Dakota. It was in force for 31 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, 6:14 PM CDT (23:14 UTC)
Expired
Oct 9, 2021, 6:45 PM CDT
In force
31 min
Issued by
NWS Aberdeen, SD
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

Counties Marshall County, SD, Roberts County, SD

The radar

The Aberdeen radar (KABR), 99 km from the middle of the area, began a volume at 23:15 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, 6:44 PM CDTTSTM WND GST 7010 S Lidgerwood, SDTRAINED SPOTTER REPORTS 70MPH WIND GUSTS

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, 11.2 hours before the alert went out and 135 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.

941 
WFUS53 KABR 092314
TORABR
SDC091-109-092345-
/O.NEW.KABR.TO.W.0017.211009T2314Z-211009T2345Z/

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

The National Weather Service in Aberdeen has issued a

* Tornado Warning for...
  Northwestern Roberts County in northeastern South Dakota...
  Northeastern Marshall County in northeastern South Dakota...

* Until 645 PM CDT.
    
* At 613 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Sica Hollow State Park, or 12 miles northwest 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...
  Veblen and Veblen Flats Housing around 625 PM CDT.

Other locations in the path of this tornadic thunderstorm include
Claire City.

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 4573 9688 4553 9721 4573 9736 4593 9766
      4594 9763 4593 9696
TIME...MOT...LOC 2313Z 216DEG 27KT 4576 9727 

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

$$

Connelly
1 follow-up statement
109 
WWUS53 KABR 092342
SVSABR

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

SDC091-109-092351-
/O.EXP.KABR.TO.W.0017.000000T0000Z-211009T2345Z/
Roberts SD-Marshall SD-
642 PM CDT Sat Oct 9 2021

...THE TORNADO WARNING FOR NORTHWESTERN ROBERTS AND NORTHEASTERN
MARSHALL COUNTIES WILL EXPIRE AT 645 PM CDT...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.

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

LAT...LON 4573 9688 4553 9721 4573 9736 4593 9766
      4594 9763 4593 9696
TIME...MOT...LOC 2341Z 216DEG 27KT 4592 9710 

$$

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, 6:15 PM CDTSevere Thunderstorm WarningABRCodington, Day, Deuel, Grant, Hamlin, Marshall and 1 more60 min
Oct 9, 6:28 PM CDTTornado WarningABRRoberts21 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.