Alert archive / South Dakota / Tornado Warnings in 2020

Tornado Warning 18, NWS Sioux Falls, SD

August 30, 2020Beadle County, South Dakota

NWS Sioux Falls, SD issued this tornado warning at Aug 30, 2020, 7:23 PM CDT for Beadle County, South Dakota. It was in force for 17 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 30, 2020, 7:23 PM CDT (00:23 UTC)
Expired
Aug 30, 2020, 7:40 PM CDT
In force
17 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Tornado
Observed
Hail
0.75 in

County Beadle County, SD

The radar

The Aberdeen radar (KABR), 132 km from the middle of the area, began a volume at 00:26 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 30, 4:55 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 0.4 hours before the alert went out and 70 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 00:00Z on 2020-08-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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 00:00Z on 2020-08-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 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
5 J/kg
Mixed-layer CIN
-191 J/kg
Mixed-layer LCL
914 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
97 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-1.2

Open this sounding in Storm Lab

The text

As transmitted.

795 
WFUS53 KFSD 310023
TORFSD
SDC005-310100-
/O.NEW.KFSD.TO.W.0018.200831T0023Z-200831T0100Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Sioux Falls SD
723 PM CDT Sun Aug 30 2020

The National Weather Service in Sioux Falls has issued a

* Tornado Warning for...
  Southeastern Beadle County in east central South Dakota...

* Until 800 PM CDT.

* At 723 PM CDT, a confirmed tornado was located near Virgil, or near
  Huron, moving east at 35 mph.

  HAZARD...Damaging tornado.

  SOURCE...Law enforcement confirmed tornado.

  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.

* The tornado will be near...
  Huron around 730 PM CDT.
  Cavour around 745 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

This cluster of thunderstorms is capable of producing tornadoes and
widespread significant wind damage. Do not wait to see or hear the
tornado. For your protection move to an interior room on the lowest
floor of a building.

&&

LAT...LON 4420 9840 4438 9840 4443 9792 4420 9792
TIME...MOT...LOC 0023Z 265DEG 32KT 4429 9830 

TORNADO...OBSERVED
HAIL...<.75IN

$$

VandenBoogart
2 follow-up statements
390 
WWUS53 KFSD 310037
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
737 PM CDT Sun Aug 30 2020

SDC005-310100-
/O.CON.KFSD.TO.W.0018.000000T0000Z-200831T0100Z/
Beadle SD-
737 PM CDT Sun Aug 30 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 800 PM CDT FOR
SOUTHEASTERN BEADLE COUNTY...
    
At 735 PM CDT, radar continues to indicate broad rotation with a 
storm that previously produced a confirmed tornado. This storm is 
currently located south of Huron, moving east at 30 mph.

HAZARD...Damaging tornado.

SOURCE...Law enforcement confirmed tornado.

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 tornado will be near...
  Cavour around 750 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

This cluster of thunderstorms is capable of producing tornadoes and
widespread significant wind damage. Do not wait to see or hear the
tornado. For your protection move to an interior room on the lowest
floor of a building.

&&

LAT...LON 4423 9826 4433 9827 4439 9792 4422 9792
TIME...MOT...LOC 0035Z 264DEG 26KT 4429 9818 

TORNADO...OBSERVED
HAIL...<.75IN

$$

VandenBoogart
593 
WWUS53 KFSD 310040
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
740 PM CDT Sun Aug 30 2020

SDC005-310050-
/O.CAN.KFSD.TO.W.0018.000000T0000Z-200831T0100Z/
Beadle SD-
740 PM CDT Sun Aug 30 2020

...THE TORNADO WARNING FOR SOUTHEASTERN BEADLE COUNTY IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been cancelled.  However gusty winds and
heavy rain are still possible with this thunderstorm.

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

LAT...LON 4423 9826 4433 9827 4439 9792 4422 9792
TIME...MOT...LOC 0038Z 265DEG 32KT 4429 9812 

$$

VandenBoogart

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 30, 7:06 PM CDTTornado WarningFSDBeadle24 min
Aug 30, 7:29 PM CDTSevere Thunderstorm WarningFSDAurora, Jerauld46 min
Aug 30, 8:12 PM CDTSevere Thunderstorm WarningFSDAurora, Jerauld, Sanborn20 min
Aug 31, 4:02 AM CDTSevere Thunderstorm WarningFSDUnion28 min

Nearby

Tornado Warnings in South Dakota, 2020Every tornado warning in 2020Tornadoes 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.