Alert archive / South Dakota / Tornado Warnings in 2020

Tornado Warning 15, NWS Sioux Falls, SD

August 28, 2020Brookings County, Kingsbury County, South Dakota

NWS Sioux Falls, SD issued this tornado warning at Aug 28, 2020, 1:50 AM CDT for Brookings County, Kingsbury County, South Dakota. It was in force for 25 min. 3 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: Aug 28, 2020, 1:50 AM CDT (06:50 UTC)
Expired: Aug 28, 2020, 2:15 AM CDT
In force: 25 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

Counties Brookings County, SD, Kingsbury County, SD

The radar

The Sioux Falls radar (KFSD), 96 km from the middle of the area, began a volume at 06:53 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

Time	Report	Where	Remark
Aug 28, 1:52 AM CDT	TSTM WND DMG	Badger, SD	2-6 INCH BRANCHES DOWN.
Aug 28, 1:55 AM CDT	TSTM WND DMG	5 Ne Arlington, SD	SOCIAL MEDIA PICTURE SHARED OF TREE CRUSHING A SWING SET. NOTED THAT SEVERAL TREES WERE DOWN ON PROPERTY.
Aug 28, 2:03 AM CDT	TSTM WND DMG	Bruce, SD	REPORTED TREE DAMAGE IN TOWN.

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.

Issued	Product	Office	Lasted
Aug 27, 10:20 PM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 6.8 hours before the alert went out and 129 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: 451 J/kg
Mixed-layer CIN: -200 J/kg
Mixed-layer LCL: 1389 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 140 m²/s²
0-3 km storm-relative helicity: 218 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

277 
WFUS53 KFSD 280650
TORFSD
SDC011-077-280715-
/O.NEW.KFSD.TO.W.0015.200828T0650Z-200828T0715Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Sioux Falls SD
150 AM CDT Fri Aug 28 2020

The National Weather Service in Sioux Falls has issued a

* Tornado Warning for...
  Northeastern Kingsbury County in east central South Dakota...
  Northern Brookings County in east central South Dakota...

* Until 215 AM CDT.

* At 150 AM CDT, severe thunderstorms capable of producing both
  tornadoes and extensive straight line wind damage were located near
  Arlington, or 15 miles northeast of Lake Thompson State Recreation
  Area, moving east at 60 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.

* These dangerous storms will be near...
  Lake Poinsett around 155 AM CDT.
  Oakwood State Park around 200 AM CDT.
  Bruce around 205 AM CDT.
  White around 215 AM 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 4436 9655 4431 9725 4452 9731 4455 9714
      4454 9661
TIME...MOT...LOC 0650Z 258DEG 50KT 4442 9716 

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

$$

SG

1 follow-up statement

220 
WWUS53 KFSD 280703
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
203 AM CDT Fri Aug 28 2020

SDC077-280713-
/O.CAN.KFSD.TO.W.0015.000000T0000Z-200828T0715Z/
Kingsbury SD-
203 AM CDT Fri Aug 28 2020

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

A Severe Thunderstorm Watch remains in effect until 500 AM CDT for
east central South Dakota.

LAT...LON 4433 9698 4454 9703 4454 9661 4436 9655
TIME...MOT...LOC 0703Z 260DEG 54KT 4445 9689 

$$

SDC011-280715-
/O.CON.KFSD.TO.W.0015.000000T0000Z-200828T0715Z/
Brookings SD-
203 AM CDT Fri Aug 28 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 215 AM CDT FOR NORTHERN
BROOKINGS COUNTY...

At 203 AM CDT, a severe squall line capable of producing both
tornadoes and extensive straight line wind damage was located over
Bruce, or 8 miles south of Estelline, moving east at 60 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.

These dangerous storms will be near...
  White around 215 AM 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 4433 9698 4454 9703 4454 9661 4436 9655
TIME...MOT...LOC 0703Z 260DEG 54KT 4445 9689 

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

$$

SG

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 28, 12:27 AM CDT	Severe Thunderstorm Warning	FSD	Beadle, Jerauld, Sanborn	63 min
Aug 28, 1:02 AM CDT	Severe Thunderstorm Warning	FSD	Beadle, Sanborn	28 min
Aug 28, 1:05 AM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule, Davison, Sanborn	25 min
Aug 28, 1:09 AM CDT	Severe Thunderstorm Warning	FSD	Brookings, Kingsbury, Lake, Miner	66 min
Aug 28, 1:19 AM CDT	Tornado Warning	FSD	Kingsbury	26 min
Aug 28, 1:22 AM CDT	Tornado Warning	FSD	Kingsbury	38 min
Aug 28, 1:28 AM CDT	Severe Thunderstorm Warning	FSD	Hanson, McCook	62 min
Aug 28, 2:01 AM CDT	Severe Thunderstorm Warning	FSD	Brookings, Lake, Moody	59 min
Aug 28, 2:15 AM CDT	Tornado Warning	FSD	Brookings	30 min

Nearby

Tornado Warnings in South Dakota, 2020 Every tornado warning in 2020 Tornadoes in 2020

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.