Alert archive / South Dakota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 97, NWS Sioux Falls, SD

August 22, 20214 counties in South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 22, 2021, 8:06 PM CDT for 4 counties in South Dakota. It was in force for 39 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, 8:06 PM CDT (01:06 UTC)
Expired: Aug 22, 2021, 8:45 PM CDT
In force: 39 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Damage threat: Considerable
Hail: 1.75 in
Wind: 70.0 mph

Counties Davison County, SD, Hanson County, SD, Miner County, SD, Sanborn County, SD

The radar

The Sioux Falls radar (KFSD), 86 km from the middle of the area, began a volume at 01:04 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.

Issued	Product	Office	Lasted
Aug 22, 3:36 PM CDT	Severe Thunderstorm Watch	SPC	5 hr
Aug 22, 6:31 PM CDT	Tornado Watch	SPC	3 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 1.1 hours before the alert went out and 134 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: 166 J/kg
Mixed-layer CIN: -152 J/kg
Mixed-layer LCL: 1323 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 245 m²/s²
0-3 km storm-relative helicity: 282 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.4

Open this sounding in Storm Lab

The text

As transmitted.

284 
WUUS53 KFSD 230106
SVRFSD
SDC035-061-097-111-230145-
/O.NEW.KFSD.SV.W.0097.210823T0106Z-210823T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
806 PM CDT Sun Aug 22 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Northeastern Davison County in southeastern South Dakota...
  Southeastern Sanborn County in east central South Dakota...
  Southwestern Miner County in east central South Dakota...
  Northern Hanson County in southeastern South Dakota...

* Until 845 PM CDT.

* At 805 PM CDT, a severe thunderstorm was located near Loomis, or 7
  miles north of Mitchell, moving east at 30 mph.

  HAZARD...Golf ball size hail and 70 mph wind gusts.

  SOURCE...Trained weather spotters.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           considerable tree damage. Wind damage is also likely to 
           mobile homes, roofs, and outbuildings.

* This severe thunderstorm will be near...
  Fulton around 825 PM CDT.
  Farmer around 840 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

For your protection move to an interior room on the lowest floor of a
building.

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

&&

LAT...LON 4391 9762 4371 9760 4371 9761 4362 9761
      4372 9817 4392 9809
TIME...MOT...LOC 0105Z 279DEG 27KT 4383 9802 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Schumacher

2 follow-up statements

995 
WWUS53 KFSD 230122
SVSFSD

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

SDC035-230131-
/O.CAN.KFSD.SV.W.0097.000000T0000Z-210823T0145Z/
Davison SD-
822 PM CDT Sun Aug 22 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN DAVISON COUNTY IS
CANCELLED...
    
The severe 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 southeastern
and east central South Dakota.

LAT...LON 4391 9762 4372 9760 4362 9761 4367 9790
      4369 9797 4391 9797
TIME...MOT...LOC 0121Z 275DEG 33KT 4375 9784 

$$

SDC061-097-111-230145-
/O.CON.KFSD.SV.W.0097.000000T0000Z-210823T0145Z/
Sanborn SD-Miner SD-Hanson SD-
822 PM CDT Sun Aug 22 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 PM CDT
FOR SOUTHEASTERN SANBORN...SOUTHWESTERN MINER AND NORTHERN HANSON
COUNTIES...

At 821 PM CDT, a severe thunderstorm was located over Fulton, or 9
miles east of Mitchell, moving east at 40 mph.

HAZARD...Golf ball size hail and 60 mph wind gusts.

SOURCE...Trained weather spotters.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

This severe storm will be near...
  Alexandria around 825 PM CDT.

Other locations in the path of this severe thunderstorm include
Farmer.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4391 9762 4372 9760 4362 9761 4367 9790
      4369 9797 4391 9797
TIME...MOT...LOC 0121Z 275DEG 33KT 4375 9784 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Schumacher

261 
WWUS53 KFSD 230147
SVSFSD

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

SDC061-097-111-230156-
/O.EXP.KFSD.SV.W.0097.000000T0000Z-210823T0145Z/
Sanborn SD-Miner SD-Hanson SD-
847 PM CDT Sun Aug 22 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SANBORN...
SOUTHWESTERN MINER AND NORTHERN HANSON COUNTIES HAS EXPIRED...
        
The storm which prompted the warning no longer threatens Sanborn, 
Miner or western Hanson Counties. Therefore, the warning has been 
allowed to expire.

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

Remember, a Severe Thunderstorm Warning still remains in effect for
eastern Hanson County until 915 PM CDT.

LAT...LON 4391 9762 4372 9760 4362 9761 4367 9790
      4369 9797 4391 9797
TIME...MOT...LOC 0146Z 279DEG 27KT 4372 9762 

$$

Schumacher

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 22, 7:15 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Davison, Hanson, Miner, Sanborn	30 min
Aug 22, 7:21 PM CDT	Severe Thunderstorm Warning	FSD	Aurora	24 min
Aug 22, 7:31 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Davison, Sanborn	44 min
Aug 22, 8:32 PM CDT	Severe Thunderstorm Warning	FSD	Hanson, McCook	43 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2021 Every severe thunderstorm warning 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.