Alert archive / South Dakota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 11, NWS Sioux Falls, SD

May 23, 2021Brule County, Charles Mix County, Gregory County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 23, 2021, 10:17 PM CDT for Brule County, Charles Mix County, Gregory County, South Dakota. It was in force for 43 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: May 23, 2021, 10:17 PM CDT (03:17 UTC)
Expired: May 23, 2021, 11:00 PM CDT
In force: 43 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Brule County, SD, Charles Mix County, SD, Gregory County, SD

The radar

The Sioux Falls radar (KFSD), 211 km from the middle of the area, began a volume at 03:19 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 nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 3.3 hours before the alert went out and 157 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: 407 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 2081 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 97 m²/s²
0-3 km storm-relative helicity: 173 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.5

Open this sounding in Storm Lab

The text

As transmitted.

430 
WUUS53 KFSD 240317
SVRFSD
SDC015-023-053-240400-
/O.NEW.KFSD.SV.W.0011.210524T0317Z-210524T0400Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
1017 PM CDT Sun May 23 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Northwestern Charles Mix County in south central South Dakota...
  Northwestern Gregory County in south central South Dakota...
  Central Brule County in south central South Dakota...

* Until 1100 PM CDT.

* At 1016 PM CDT, severe thunderstorms were located along a line
  extending from 11 miles south of Lyman to 6 miles southeast of
  Hamill to near Dallas, moving northeast at 50 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Severe thunderstorms will be near...
  Lake Francis Case around 1030 PM CDT.
  Chamberlain around 1045 PM CDT.

Other locations impacted by these severe thunderstorms include Dixon
in Gregory County and Pukwana in Brule County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a DANGEROUS SITUATION. These storms are producing widespread 
wind damage across portions of Lyman and Tripp counties. SEEK 
SHELTER NOW inside a sturdy structure and stay away from windows! 
&&

LAT...LON 4350 9953 4350 9929 4352 9928 4357 9934
      4364 9936 4366 9938 4365 9945 4367 9947
      4369 9945 4370 9941 4377 9941 4380 9936
      4386 9931 4390 9936 4392 9936 4393 9910
      4390 9906 4340 9895 4314 9953
TIME...MOT...LOC 0316Z 225DEG 45KT 4372 9976 4353 9958 4321 9958 

HAIL...<.75IN
WIND...60MPH
 
$$

Chapman

3 follow-up statements

634 
WWUS53 KFSD 240333
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1033 PM CDT Sun May 23 2021

SDC015-023-053-240400-
/O.CON.KFSD.SV.W.0011.000000T0000Z-210524T0400Z/
Charles Mix SD-Gregory SD-Brule SD-
1033 PM CDT Sun May 23 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM CDT
FOR NORTHWESTERN CHARLES MIX...NORTHWESTERN GREGORY AND CENTRAL BRULE
COUNTIES...

At 1031 PM CDT, severe thunderstorms were located along a line
extending from near Reliance to 7 miles south of Lake Francis Case to
10 miles northeast of Gregory, moving northeast at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe storms will be near...
  Chamberlain around 1040 PM CDT.

Other locations impacted by these severe thunderstorms include Dixon
In Gregory County and Pukwana.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a DANGEROUS SITUATION. These storms are producing widespread 
wind damage across Lyman county. There were reports of trucks blown 
off Interstate 90 near Presho around 940 pm CDT. SEEK SHELTER NOW 
inside a sturdy structure and stay away from windows.
 
&&

LAT...LON 4350 9953 4350 9929 4352 9928 4357 9934
      4364 9936 4366 9938 4365 9945 4367 9947
      4369 9945 4370 9941 4377 9941 4380 9936
      4386 9931 4390 9936 4392 9936 4393 9910
      4390 9906 4340 9895 4314 9953
TIME...MOT...LOC 0331Z 226DEG 48KT 4385 9953 4366 9935 4335 9928 

HAIL...<.75IN
WIND...60MPH
 
$$

Chapman

289 
WWUS53 KFSD 240349
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1049 PM CDT Sun May 23 2021

SDC053-240359-
/O.CAN.KFSD.SV.W.0011.000000T0000Z-210524T0400Z/
Gregory SD-
1049 PM CDT Sun May 23 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN GREGORY COUNTY IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 4393 9910 4390 9906 4340 9895 4336 9910
      4346 9919 4358 9926 4374 9925 4387 9931
      4390 9936 4392 9936
TIME...MOT...LOC 0349Z 227DEG 42KT 4401 9929 4382 9912 4350 9905 

$$

SDC015-023-240400-
/O.CON.KFSD.SV.W.0011.000000T0000Z-210524T0400Z/
Charles Mix SD-Brule SD-
1049 PM CDT Sun May 23 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM CDT
FOR NORTHWESTERN CHARLES MIX AND CENTRAL BRULE COUNTIES...

At 1049 PM CDT, severe thunderstorms were located along a line
extending from near Crow Creek Housing to 9 miles northwest of
Kimball to 13 miles northwest of Platte, moving northeast at 50 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe thunderstorms will remain over mainly rural areas of
northwestern Charles Mix and central Brule Counties, including the
following locations... Pukwana.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4393 9910 4390 9906 4340 9895 4336 9910
      4346 9919 4358 9926 4374 9925 4387 9931
      4390 9936 4392 9936
TIME...MOT...LOC 0349Z 227DEG 42KT 4401 9929 4382 9912 4350 9905 

HAIL...<.75IN
WIND...60MPH
 
$$

Chapman

651 
WWUS53 KFSD 240402
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1102 PM CDT Sun May 23 2021

SDC015-023-240410-
/O.EXP.KFSD.SV.W.0011.000000T0000Z-210524T0400Z/
Charles Mix SD-Brule SD-
1102 PM CDT Sun May 23 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN CHARLES MIX AND
CENTRAL BRULE COUNTIES HAS EXPIRED...
    
The storms which prompted the warning have weakened below severe
limits, and have exited the warned area. Therefore, the warning has 
been allowed to expire.  However, gusty winds to 40 to 50 mph are 
still possible with these thunderstorms as they move through areas 
toward Wessington Springs to White Lake through 1130 pm CDT.

LAT...LON 4393 9910 4390 9906 4340 9895 4336 9910
      4346 9919 4358 9926 4374 9925 4387 9931
      4390 9936 4392 9936
TIME...MOT...LOC 0400Z 225DEG 45KT 4411 9915 4392 9898 4360 9891 

$$

Chapman

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.