Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 102, NWS Sioux Falls, SD

August 24, 20214 counties in Minnesota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 24, 2021, 10:00 AM CDT for 4 counties in Minnesota. It was in force for 45 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 24, 2021, 10:00 AM CDT (15:00 UTC)
Expired
Aug 24, 2021, 10:45 AM CDT
In force
45 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Cottonwood County, MN, Jackson County, MN, Nobles County, MN, Rock County, MN

The radar

The Sioux Falls radar (KFSD), 118 km from the middle of the area, began a volume at 14:59 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 24, 10:46 AM CDTHAIL 0.78 E Round Lake, MNDICKENSON COUNTY EM REPORTED DIME TO NICKLE SIZED HAIL NEAR SIOUX VALLEY, MN (ABOUT 6 MILES NORTH OF LAKEPARK IA).

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

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 3.0 hours before the alert went out and 182 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, Minneapolis, MN at 12:00Z on 2021-08-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1192 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, Minneapolis, MN at 12:00Z on 2021-08-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 141 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
1192 J/kg
Mixed-layer CIN
-180 J/kg
Mixed-layer LCL
1234 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
141 m²/s²
0-3 km storm-relative helicity
178 m²/s²
Significant tornado parameter
0.0
Supercell composite
6.9

Open this sounding in Storm Lab

The text

As transmitted.

557 
WUUS53 KFSD 241500
SVRFSD
MNC033-063-105-133-241545-
/O.NEW.KFSD.SV.W.0102.210824T1500Z-210824T1545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
1000 AM CDT Tue Aug 24 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Southeastern Rock County in southwestern Minnesota...
  Jackson County in southwestern Minnesota...
  Nobles County in southwestern Minnesota...
  Southeastern Cottonwood County in southwestern Minnesota...

* Until 1045 AM CDT.

* At 959 AM CDT, severe thunderstorms were located along a line
  extending from near Butterfield to near Heron Lake to 6 miles
  southeast of Rushmore, moving east at 30 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Worthington, Windom, Jackson In Jackson County, Mountain Lake,
  Lakefield, Adrian, Bergen, Heron Lake, Brewster, Ellsworth, Round
  Lake, Rushmore, Bingham Lake, Kilen Woods State Park, Bigelow,
  Okabena, Alpha, Wilder and Delft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4350 9500 4350 9618 4370 9586 4382 9544
      4410 9507 4410 9486 4367 9485
TIME...MOT...LOC 1459Z 263DEG 27KT 4399 9484 4379 9524 4354 9572 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

BP
1 follow-up statement
500 
WWUS53 KFSD 241523
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1023 AM CDT Tue Aug 24 2021

MNC133-241532-
/O.CAN.KFSD.SV.W.0102.000000T0000Z-210824T1545Z/
Rock MN-
1023 AM CDT Tue Aug 24 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN ROCK COUNTY IS
CANCELLED...

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

LAT...LON 4350 9500 4350 9590 4375 9568 4382 9543
      4386 9508 4400 9497 4403 9486 4367 9485
TIME...MOT...LOC 1522Z 259DEG 23KT 4383 9490 4371 9526 4354 9559 

$$

MNC033-063-105-241545-
/O.CON.KFSD.SV.W.0102.000000T0000Z-210824T1545Z/
Jackson MN-Nobles MN-Cottonwood MN-
1023 AM CDT Tue Aug 24 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 AM CDT
FOR JACKSON...EASTERN NOBLES AND SOUTHEASTERN COTTONWOOD COUNTIES...

At 1022 AM CDT, severe thunderstorms were located along a line 
extending from near Bergen to near Lakefield to near Round Lake, 
moving east at 25 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Worthington, Windom, Jackson In Jackson County, Mountain Lake,
Lakefield, Bergen, Heron Lake, Brewster, Round Lake, Rushmore,
Bingham Lake, Kilen Woods State Park, Bigelow, Okabena, Alpha and
Wilder.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4350 9500 4350 9590 4375 9568 4382 9543
      4386 9508 4400 9497 4403 9486 4367 9485
TIME...MOT...LOC 1522Z 259DEG 23KT 4383 9490 4371 9526 4354 9559 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

BP

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 24, 8:16 AM CDTSevere Thunderstorm WarningFSDCottonwood, Murray44 min
Aug 24, 8:59 AM CDTSevere Thunderstorm WarningFSDCottonwood, Murray61 min
Aug 24, 9:43 AM CDTSevere Thunderstorm WarningFSDNobles47 min
Aug 24, 10:44 AM CDTSevere Thunderstorm WarningFSDJackson, Nobles30 min

Nearby

Severe 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.