Alert archive / Nebraska / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 82, NWS Sioux Falls, SD

August 6, 2021Dakota County, Nebraska; Union County, South Dakota; Woodbury County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 6, 2021, 12:10 AM CDT for Dakota County, Nebraska; Union County, South Dakota; Woodbury County, Iowa. It was in force for 35 min. 1 report 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
Aug 6, 2021, 12:10 AM CDT (05:10 UTC)
Expired
Aug 6, 2021, 12:45 AM CDT
In force
35 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Woodbury County, IA, Dakota County, NE, Union County, SD

The radar

The Omaha radar (KOAX), 109 km from the middle of the area, began a volume at 05:11 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
Aug 6, 12:22 AM CDTTSTM WND DMG3 Se Sioux City, IACORRECTS PREVIOUS TSTM WND DMG REPORT FROM 3 SE SIOUX CITY. PICTURE VIA SOCIAL MEDIA OF A FEW 4-6 INCH TREE BRANCHES DOWN IN THE MORNINGSIDE NEIGHBORHOOD. TIME ESTIMATED VIA RADAR.

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 334 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 2021-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 835 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Aberdeen, SD at 00:00Z on 2021-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 square meters per square second.193958Sfc1 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
835 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
1549 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
259 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

695 
WUUS53 KFSD 060510
SVRFSD
IAC193-NEC043-SDC127-060600-
/O.NEW.KFSD.SV.W.0082.210806T0510Z-210806T0600Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
1210 AM CDT Fri Aug 6 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Southwestern Woodbury County in west central Iowa...
  Eastern Dakota County in northeastern Nebraska...
  Southeastern Union County in southeastern South Dakota...

* Until 100 AM CDT.

* At 1209 AM CDT, a severe thunderstorm was located over Dakota City,
  or near Sioux City, moving southeast at 30 mph.

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

  SOURCE...Radar indicated.

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

* This severe thunderstorm will be near...
  Sergeant Bluff around 1220 AM CDT.
  Salix around 1235 AM CDT.
  Sloan around 1245 AM CDT.
  Hornick around 1255 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4223 9633 4225 9633 4227 9634 4228 9646
      4243 9667 4257 9653 4227 9598 4221 9613
      4222 9634
TIME...MOT...LOC 0509Z 310DEG 24KT 4241 9645 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Chapman
2 follow-up statements
026 
WWUS53 KFSD 060539
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1239 AM CDT Fri Aug 6 2021

SDC127-060542-
/O.CAN.KFSD.SV.W.0082.000000T0000Z-210806T0600Z/
Union SD-
1239 AM CDT Fri Aug 6 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN UNION COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4223 9633 4225 9633 4227 9634 4228 9646
      4241 9647 4247 9639 4227 9598 4221 9613
      4222 9634
TIME...MOT...LOC 0532Z 307DEG 18KT 4236 9635 

$$

IAC193-NEC043-060600-
/O.CON.KFSD.SV.W.0082.000000T0000Z-210806T0600Z/
Woodbury IA-Dakota NE-
1239 AM CDT Fri Aug 6 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 100 AM CDT
FOR SOUTHWESTERN WOODBURY AND SOUTHEASTERN DAKOTA COUNTIES...

At 1232 AM CDT, a severe thunderstorm was located over Sergeant
Bluff, or 9 miles south of Sioux City, moving southeast at 20 mph.

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

SOURCE...Radar indicated.

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

This severe storm will be near...
  Salix around 1245 AM CDT.
  Sloan around 100 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4223 9633 4225 9633 4227 9634 4228 9646
      4241 9647 4247 9639 4227 9598 4221 9613
      4222 9634
TIME...MOT...LOC 0532Z 307DEG 18KT 4236 9635 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Chapman
799 
WWUS53 KFSD 060545
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1245 AM CDT Fri Aug 6 2021

IAC193-NEC043-060555-
/O.CAN.KFSD.SV.W.0082.000000T0000Z-210806T0600Z/
Woodbury IA-Dakota NE-
1245 AM CDT Fri Aug 6 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN WOODBURY AND
SOUTHEASTERN DAKOTA COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However gusty winds are
still possible with this thunderstorm.

LAT...LON 4223 9633 4225 9633 4227 9634 4228 9646
      4241 9647 4247 9639 4227 9598 4221 9613
      4222 9634
TIME...MOT...LOC 0544Z 310DEG 24KT 4230 9626 

$$

Chapman

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 7:00 PM CDTSevere Thunderstorm WarningFSDLake, Moody45 min
Aug 5, 7:28 PM CDTSevere Thunderstorm WarningFSDBrookings, Moody32 min
Aug 5, 7:44 PM CDTSevere Thunderstorm WarningFSDMoody33 min
Aug 5, 7:58 PM CDTSevere Thunderstorm WarningFSDLake, Minnehaha, Moody47 min
Aug 5, 8:24 PM CDTSevere Thunderstorm Warning Considerable damage threatFSDMinnehaha, Moody51 min
Aug 5, 8:57 PM CDTSevere Thunderstorm Warning Considerable damage threatFSDLincoln, Minnehaha48 min
Aug 5, 9:04 PM CDTSevere Thunderstorm WarningFSDMinnehaha28 min
Aug 5, 10:04 PM CDTSevere Thunderstorm WarningFSDLincoln, McCook, Minnehaha, Turner41 min
Aug 5, 10:36 PM CDTSevere Thunderstorm WarningFSDClay, Lincoln, Turner, Union39 min
Aug 5, 11:40 PM CDTSevere Thunderstorm WarningFSDMinnehaha50 min
Aug 6, 1:06 AM CDTSevere Thunderstorm WarningFSDLincoln39 min
Aug 6, 1:36 AM CDTSevere Thunderstorm WarningFSDUnion24 min
Aug 5, 9:31 PM CDTSevere Thunderstorm WarningFSDLyon, Sioux44 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2021Severe Thunderstorm Warnings in South Dakota, 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.