Alert archive / South Dakota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 160, NWS Sioux Falls, SD

September 17, 20215 counties in South Dakota; Lincoln County, Pipestone County, Rock County, Minnesota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Sep 17, 2021, 12:10 AM CDT for 5 counties in South Dakota; Lincoln County, Pipestone County, Rock County, Minnesota. It was in force for 35 min. 6 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
Sep 17, 2021, 12:10 AM CDT (05:10 UTC)
Expired
Sep 17, 2021, 12:45 AM CDT
In force
35 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Damage threat
Considerable
Hail
0.75 in
Wind
70.0 mph

Counties Lincoln County, MN, Pipestone County, MN, Rock County, MN, Brookings County, SD, Lake County, SD, McCook County, SD, Minnehaha County, SD, Moody County, SD

The radar

The Sioux Falls radar (KFSD), 42 km from the middle of the area, began a volume at 05:10 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

TimeReportWhereRemark
Sep 17, 12:12 AM CDTTSTM WND DMGCrooks, SDSEVERAL ROWS OF SHINGLES BLOWN OFF OF HOUSE AND GARAGE. NEIGHBOR ALSO HAD LARGE TREE BLOWN DOWN IN FRONT YARD.
Sep 17, 12:15 AM CDTTSTM WND GST 733 Se Baltic, SDMESONET STATION BTCS2 BALTIC 3 SE (SD MESONET).
Sep 17, 12:19 AM CDTTSTM WND DMG4 S Colton, SDREPORT FROM MPING: 1-INCH TREE LIMBS BROKEN; SHINGLES BLOWN OFF.
Sep 17, 12:20 AM CDTTSTM WND GST 6410 Ssw Aurora, SDMESONET STATION 224 SD RWIS WARD.
Sep 17, 12:30 AM CDTTSTM WND GST 601 Nnw Pipestone, MNMESONET STATION RPPM5 REDSTONE RAWS.
Sep 17, 12:37 AM CDTTSTM WND GST 591 Wsw Beaver Creek, MNMESONET STATION MN006 BEAVER CREEK I-90 MILE POST 4.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 5.2 hours before the alert went out and 185 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 2021-09-17Temperature 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 00:00Z on 2021-09-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -170 square meters per square second.1939587897Sfc1 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
1789 m above ground
0-6 km bulk shear
75 kt
0-1 km storm-relative helicity
-170 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

371 
WUUS53 KFSD 170510
SVRFSD
MNC081-117-133-SDC011-079-087-099-101-170545-
/O.NEW.KFSD.SV.W.0160.210917T0510Z-210917T0545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
1210 AM CDT Fri Sep 17 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Southern Lincoln County in southwestern Minnesota...
  Northwestern Rock County in southwestern Minnesota...
  Pipestone County in southwestern Minnesota...
  Moody County in east central South Dakota...
  Southeastern Lake County in east central South Dakota...
  Minnehaha County in southeastern South Dakota...
  Southeastern McCook County in southeastern South Dakota...
  Southeastern Brookings County in east central South Dakota...

* Until 1245 AM CDT.

* At 1210 AM CDT, severe thunderstorms were located along a line
  extending from 6 miles south of Aurora to near Colman to near
  Hartford, moving east at 55 mph.

  HAZARD...70 mph wind gusts. The strongest gusts are occurring 
           ahead of the main line of storms.

  SOURCE...Radar indicated.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Severe thunderstorms will be near...
  Aurora around 1215 AM CDT.
  Baltic, Egan and Trent around 1220 AM CDT.
  Elkton and Ward around 1225 AM CDT.
  Brandon, Jasper and Palisades State Park around 1230 AM CDT.
  Garretson, Lake Benton and Sherman around 1235 AM CDT.
  Pipestone, Beaver Creek, Trosky and Pipestone National Monument 
  around 1240 AM CDT.
  Tyler and Holland around 1245 AM CDT.

Other locations impacted by these severe thunderstorms include Ihlen
and Flandreau Santee Sioux Tribal Nation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4394 9623 4355 9640 4353 9720 4425 9687
      4438 9609
TIME...MOT...LOC 0510Z 259DEG 47KT 4418 9671 4390 9681 4366 9692 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

SG

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 16, 10:20 PM CDTSevere Thunderstorm WarningFSDCharles Mix, Gregory25 min
Sep 16, 11:31 PM CDTSevere Thunderstorm WarningFSDBon Homme, Charles Mix, Hutchinson, Yankton29 min
Sep 17, 12:29 AM CDTSevere Thunderstorm WarningFSDClay, Lincoln, Turner, Union, Yankton46 min
Sep 17, 12:34 AM CDTSevere Thunderstorm Warning Considerable damage threatFSDMinnehaha56 min
Sep 17, 12:36 AM CDTSevere Thunderstorm Warning Considerable damage threatFSDLincoln, Minnehaha54 min
Sep 17, 1:11 AM CDTSevere Thunderstorm WarningFSDUnion49 min
Sep 17, 1:21 AM CDTSevere Thunderstorm WarningFSDCottonwood, Jackson, Lyon, Murray, Nobles39 min
Sep 17, 1:23 AM CDTSevere Thunderstorm WarningFSDJackson, Nobles67 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2021Severe Thunderstorm Warnings in Minnesota, 2021Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.