Alert archive / South Dakota / Tornado Warnings in 2021

Tornado Warning 6, NWS Sioux Falls, SD

August 22, 2021Aurora County, Davison County, Sanborn County, South Dakota

NWS Sioux Falls, SD issued this tornado warning at Aug 22, 2021, 6:47 PM CDT for Aurora County, Davison County, Sanborn County, South Dakota. It was in force for 32 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
Aug 22, 2021, 6:47 PM CDT (23:47 UTC)
Expired
Aug 22, 2021, 7:19 PM CDT
In force
32 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Tornado
Radar indicated
Hail
2.5 in

Counties Aurora County, SD, Davison County, SD, Sanborn County, SD

The radar

The Sioux Falls radar (KFSD), 116 km from the middle of the area, began a volume at 23:49 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.

IssuedProductOfficeLasted
Aug 22, 3:36 PM CDTSevere Thunderstorm WatchSPC5 hr
Aug 22, 6:31 PM CDTTornado WatchSPC3 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 11.8 hours before the alert went out and 119 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 2021-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 135 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1388 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
135 m²/s²
0-3 km storm-relative helicity
261 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

962 
WFUS53 KFSD 222347
TORFSD
SDC003-035-111-230030-
/O.NEW.KFSD.TO.W.0006.210822T2347Z-210823T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Sioux Falls SD
647 PM CDT Sun Aug 22 2021

The National Weather Service in Sioux Falls has issued a

* Tornado Warning for...
  Northern Davison County in southeastern South Dakota...
  Southwestern Sanborn County in east central South Dakota...
  Northeastern Aurora County in south central South Dakota...

* Until 730 PM CDT.
    
* At 647 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Storla, or 11 miles north of Plankinton, moving
  east at 30 mph.

  HAZARD...Tornado and tennis ball size hail.

  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...
  Storla around 655 PM CDT.
  Letcher around 710 PM CDT.
  Loomis around 715 PM CDT.
  Mitchell around 725 PM CDT.

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 4389 9795 4385 9796 4385 9797 4381 9796
      4367 9799 4383 9849 4394 9848 4394 9839
TIME...MOT...LOC 2347Z 279DEG 28KT 4387 9841 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...2.50 IN

$$

Schumacher
3 follow-up statements
858 
WWUS53 KFSD 230002
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
702 PM CDT Sun Aug 22 2021

SDC003-230011-
/O.CAN.KFSD.TO.W.0006.000000T0000Z-210823T0030Z/
Aurora SD-
702 PM CDT Sun Aug 22 2021

...THE TORNADO WARNING FOR NORTHEASTERN AURORA COUNTY IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 1000 PM CDT for south
central, southeastern and east central South Dakota.

LAT...LON 4388 9795 4385 9796 4385 9797 4377 9797
      4367 9799 4377 9832 4378 9832 4391 9833
TIME...MOT...LOC 0001Z 286DEG 28KT 4387 9827 

$$

SDC035-111-230030-
/O.CON.KFSD.TO.W.0006.000000T0000Z-210823T0030Z/
Davison SD-Sanborn SD-
702 PM CDT Sun Aug 22 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 PM CDT FOR NORTHERN
DAVISON AND SOUTHWESTERN SANBORN COUNTIES...
    
At 701 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Storla, or 15 miles northwest of Mitchell, moving
east at 30 mph.

HAZARD...Tornado and two inch hail.

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.

Locations impacted include...
  Letcher, Loomis and Mitchell.

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 4388 9795 4385 9796 4385 9797 4377 9797
      4367 9799 4377 9832 4378 9832 4391 9833
TIME...MOT...LOC 0001Z 286DEG 28KT 4387 9827 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...2.00 IN

$$

Schumacher
848 
WWUS53 KFSD 230012
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
712 PM CDT Sun Aug 22 2021

SDC035-111-230030-
/O.CON.KFSD.TO.W.0006.000000T0000Z-210823T0030Z/
Davison SD-Sanborn SD-
712 PM CDT Sun Aug 22 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 PM CDT FOR
NORTHEASTERN DAVISON AND SOUTH CENTRAL SANBORN COUNTIES...
    
At 712 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Loomis, or 8 miles northwest of Mitchell, moving
east at 30 mph.

HAZARD...Tornado and two inch hail.

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...
  Loomis and Mitchell around 720 PM CDT.

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 4388 9795 4385 9796 4385 9797 4377 9797
      4375 9798 4380 9826 4389 9825
TIME...MOT...LOC 0012Z 281DEG 28KT 4385 9811 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...2.00 IN

$$

Schumacher
757 
WWUS53 KFSD 230019
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
719 PM CDT Sun Aug 22 2021

SDC035-111-230029-
/O.CAN.KFSD.TO.W.0006.000000T0000Z-210823T0030Z/
Davison SD-Sanborn SD-
719 PM CDT Sun Aug 22 2021

...THE TORNADO WARNING FOR NORTHEASTERN DAVISON AND SOUTH CENTRAL
SANBORN COUNTIES 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 Tornado Watch remains in effect until 1000 PM CDT for southeastern
and east central South Dakota.

LAT...LON 4388 9795 4385 9796 4385 9797 4377 9797
      4375 9798 4380 9826 4389 9825
TIME...MOT...LOC 0017Z 279DEG 28KT 4384 9803 

$$

Schumacher

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 22, 5:15 PM CDTSevere Thunderstorm WarningFSDBrule45 min
Aug 22, 5:48 PM CDTSevere Thunderstorm WarningFSDAurora, Brule, Jerauld42 min
Aug 22, 6:23 PM CDTSevere Thunderstorm Warning Considerable damage threatFSDAurora, Jerauld40 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.