Alert archive / South Dakota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 6, NWS Sioux Falls, SD

April 5, 2021Lincoln County, Minnehaha County, South Dakota; Rock County, Minnesota; Lyon County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Apr 5, 2021, 9:27 PM CDT for Lincoln County, Minnehaha County, South Dakota; Rock County, Minnesota; Lyon County, Iowa. It was in force for 33 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
Apr 5, 2021, 9:27 PM CDT (02:27 UTC)
Expired
Apr 5, 2021, 10:00 PM CDT
In force
33 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Lyon County, IA, Rock County, MN, Lincoln County, SD, Minnehaha County, SD

The radar

The Sioux Falls radar (KFSD), 19 km from the middle of the area, began a volume at 02:28 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
Apr 5, 9:27 PM CDTHAIL 1.754 Ene Harrisburg, SDLAKE ALVIN AREA. REPORTED VIA SOCIAL MEDIA.
Apr 5, 9:40 PM CDTHAIL 11 E Larchwood, IAREPORT RECEIVED VIA SOCIAL MEDIA.
Apr 5, 9:44 PM CDTHAIL 1Larchwood, IAREPORT VIA MPING.

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, 2.5 hours before the alert went out and 216 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 2021-04-06Temperature 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 2021-04-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -70 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3053 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
-70 m²/s²
0-3 km storm-relative helicity
246 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

970 
WUUS53 KFSD 060227
SVRFSD
IAC119-MNC133-SDC083-099-060300-
/O.NEW.KFSD.SV.W.0006.210406T0227Z-210406T0300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
927 PM CDT Mon Apr 5 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Northwestern Lyon County in northwestern Iowa...
  Southwestern Rock County in southwestern Minnesota...
  Southeastern Minnehaha County in southeastern South Dakota...
  Northeastern Lincoln County in southeastern South Dakota...

* Until 1000 PM CDT.

* At 927 PM CDT, a severe thunderstorm was located over Lake Alvin
  State Recreation Area, or 7 miles southeast of Sioux Falls, moving
  northeast at 30 mph.

  HAZARD...Quarter size hail.

  SOURCE...Public. At 920 PM, there were two reports of quarter 
           sized hail on the south side of Sioux Falls, near 85th 
           St. and Louise Ave.

  IMPACT...Damage to vehicles is expected.

* This severe thunderstorm will be near...
  Rowena around 940 PM CDT.
  Larchwood around 945 PM CDT.
  Valley Springs around 950 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4332 9679 4351 9678 4367 9640 4336 9637
TIME...MOT...LOC 0227Z 245DEG 25KT 4346 9663 

HAIL...1.00IN
WIND...<50MPH
 
$$

SG
1 follow-up statement
378 
WWUS53 KFSD 060238
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
938 PM CDT Mon Apr 5 2021

IAC119-MNC133-SDC083-099-060300-
/O.CON.KFSD.SV.W.0006.000000T0000Z-210406T0300Z/
Lyon IA-Rock MN-Minnehaha SD-Lincoln SD-
938 PM CDT Mon Apr 5 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 PM CDT
FOR NORTHWESTERN LYON...SOUTHWESTERN ROCK...SOUTHEASTERN MINNEHAHA
AND NORTHEASTERN LINCOLN COUNTIES...

At 937 PM CDT, a severe thunderstorm was located near Lake Alvin
State Recreation Area, or 11 miles north of Canton, moving east at 30
mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Public.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe storm will be near...
  Larchwood and Valley Springs around 950 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4333 9672 4355 9668 4367 9640 4336 9637
TIME...MOT...LOC 0237Z 249DEG 24KT 4346 9653 

HAIL...1.00IN
WIND...60MPH
 
$$

SG

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 5, 7:03 PM CDTSevere Thunderstorm WarningFSDMcCook, Minnehaha27 min
Apr 5, 7:39 PM CDTSevere Thunderstorm WarningFSDMoody36 min
Apr 5, 7:49 PM CDTSevere Thunderstorm WarningFSDHutchinson, Turner26 min
Apr 5, 8:44 PM CDTSevere Thunderstorm WarningFSDMinnehaha31 min
Apr 5, 9:04 PM CDTSevere Thunderstorm WarningFSDLincoln, Minnehaha, Turner26 min
Apr 5, 9:48 PM CDTSevere Thunderstorm WarningFSDMinnehaha27 min
Apr 6, 9:39 AM CDTSevere Thunderstorm WarningFSDCharles Mix, Gregory10 min
Apr 5, 10:07 PM CDTSevere Thunderstorm WarningFSDNobles, Rock53 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2021Severe Thunderstorm Warnings in Minnesota, 2021Severe Thunderstorm Warnings in Iowa, 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.