Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 143, NWS Sioux Falls, SD

August 28, 2021Lincoln County, Minnehaha County, South Dakota; Lyon County, Osceola County, Sioux County, Iowa; Murray County, Nobles County, Rock County, Minnesota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 28, 2021, 8:52 PM CDT for Lincoln County, Minnehaha County, South Dakota; Lyon County, Osceola County, Sioux County, Iowa; Murray County, Nobles County, Rock County, Minnesota. It was in force for 23 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 28, 2021, 8:52 PM CDT (01:52 UTC)
Expired
Aug 28, 2021, 9:15 PM CDT
In force
23 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Lyon County, IA, Osceola County, IA, Sioux County, IA, Murray County, MN, Nobles County, MN, Rock County, MN, Lincoln County, SD, Minnehaha County, SD

The radar

The Sioux Falls radar (KFSD), 55 km from the middle of the area, began a volume at 01:56 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 28, 3:57 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 1.9 hours before the alert went out and 242 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 2021-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 143 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 2021-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 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
143 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
1242 m above ground
0-6 km bulk shear
71 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
268 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

As transmitted.

685 
WUUS53 KFSD 290152
SVRFSD
IAC119-143-167-MNC101-105-133-SDC083-099-290215-
/O.NEW.KFSD.SV.W.0143.210829T0152Z-210829T0215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
852 PM CDT Sat Aug 28 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Lyon County in northwestern Iowa...
  Northwestern Osceola County in northwestern Iowa...
  Northern Sioux County in northwestern Iowa...
  Rock County in southwestern Minnesota...
  Nobles County in southwestern Minnesota...
  South central Murray County in southwestern Minnesota...
  Southeastern Minnehaha County in southeastern South Dakota...
  Central Lincoln County in southeastern South Dakota...

* Until 915 PM CDT.

* At 851 PM CDT, severe thunderstorms were located along a line
  extending from near Hardwick to near Luverne to near Inwood to near
  Canton, moving east at 70 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Severe thunderstorms will be near...
  Luverne and Leota around 855 PM CDT.
  Adrian and Lismore around 900 PM CDT.
  Rock Rapids, Rushmore and Wilmont around 905 PM CDT.
  Rock Valley and Doon around 910 PM CDT.
  Worthington, George, Brewster, Ellsworth and Little Rock around 
  915 PM CDT.

Other locations impacted by these severe thunderstorms include
Kinbrae, Kenneth, Steen, Magnolia and Bigelow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4342 9566 4321 9593 4318 9688 4336 9668
      4365 9643 4385 9634 4385 9548 4366 9548
TIME...MOT...LOC 0151Z 259DEG 60KT 4379 9612 4363 9612 4338 9650 4326
9667

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

SG

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 28, 7:23 PM CDTSevere Thunderstorm Warning Considerable damage threatFSDLincoln52 min
Aug 28, 7:25 PM CDTSevere Thunderstorm Warning Considerable damage threatFSDHanson, Lake, McCook, Miner, Minnehaha, Moody50 min
Aug 28, 7:27 PM CDTSevere Thunderstorm WarningFSDBon Homme, Hutchinson, Turner, Yankton48 min
Aug 28, 7:48 PM CDTSevere Thunderstorm WarningFSDLake, McCook, Minnehaha, Moody, Turner31 min
Aug 28, 7:50 PM CDTSevere Thunderstorm WarningFSDBon Homme, Clay, Hutchinson, Lincoln, Turner, Yankton40 min
Aug 28, 9:13 PM CDTSevere Thunderstorm WarningFSDLincoln47 min
Aug 28, 9:20 PM CDTFlash Flood WarningFSDLincoln, Minnehaha85 min
Aug 28, 9:29 PM CDTFlash Flood WarningFSDLincoln, Minnehaha3 hr
Aug 28, 10:36 PM CDTFlash Flood WarningFSDLincoln, Minnehaha114 min
Aug 28, 11:46 PM CDTRiver Flood WarningFSDLincoln, Minnehaha8 hr
Aug 29, 7:44 AM CDTRiver Flood WarningFSDLincoln15 hr
Aug 28, 10:04 PM CDTFlash Flood WarningFSDLyon, Osceola4 hr
Aug 28, 10:24 PM CDTFlash Flood WarningFSDDickinson, Osceola5 hr
Aug 28, 7:00 PM CDTSevere Thunderstorm Warning Considerable damage threatFSDLincoln, Lyon, Murray, Pipestone45 min
Aug 28, 7:34 PM CDTSevere Thunderstorm WarningFSDLyon, Murray, Pipestone56 min
Aug 28, 8:03 PM CDTFlash Flood WarningFSDMurray, Pipestone6 hr
Aug 28, 8:06 PM CDTSevere Thunderstorm Warning Considerable damage threatFSDNobles, Rock54 min
Aug 28, 8:17 PM CDTSevere Thunderstorm Warning Considerable damage threatFSDCottonwood, Lyon, Murray58 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2021Severe Thunderstorm Warnings in Minnesota, 2021Severe Thunderstorm Warnings in South Dakota, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.