Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 100, NWS Sioux Falls, SD

August 24, 2021Cottonwood County, Murray County, Minnesota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 24, 2021, 8:59 AM CDT for Cottonwood County, Murray County, Minnesota. It was in force for 61 min. 4 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: Aug 24, 2021, 8:59 AM CDT (13:59 UTC)
Expired: Aug 24, 2021, 10:00 AM CDT
In force: 61 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Cottonwood County, MN, Murray County, MN

The radar

The Sioux Falls radar (KFSD), 117 km from the middle of the area, began a volume at 13:59 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

Time	Report	Where	Remark
Aug 24, 9:05 AM CDT	HAIL 1	6 S Westbrook, MN	CORRECTS PREVIOUS HAIL REPORT FROM 6 S WESTBROOK. SAID HE WAS AT THE INTERSECTION OF COUNTY ROAD 7 AND COUNTY ROAD 13 AND IT WAS ACTIVELY HAILING DIME TO QUARTERS. HE CALLED AT 0915 ON 24AUG.
Aug 24, 9:12 AM CDT	HAIL 1.25	Dundee, MN	SENT A PICTURE OF 1.25 INCH HAIL TO THE NWSFSD EMAIL ACCOUNT.
Aug 24, 9:21 AM CDT	HAIL 1	6 S Westbrook, MN	SAID HE WAS AT THE INTERSECTION OF COUNTY ROAD 7 AND COUNTY ROAD 13 AND IT WAS ACTIVELY HAILING DIME TO QUARTERS. HE CALLED AT 0915 ON 24AUG.
Aug 24, 9:32 AM CDT	HAIL 1	4 N Windom, MN	FB REPORT OF QUARTER SIZED HAIL 5 MILES NORTH OF WINDOM.

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, 2.0 hours before the alert went out and 170 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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.

185 
WUUS53 KFSD 241359
SVRFSD
MNC033-101-241500-
/O.NEW.KFSD.SV.W.0100.210824T1359Z-210824T1500Z/

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

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Southeastern Murray County in southwestern Minnesota...
  Cottonwood County in southwestern Minnesota...

* Until 1000 AM CDT.

* At 859 AM CDT, severe thunderstorms were located along a line
  extending from 6 miles northeast of Jeffers to Storden to near
  Fulda, moving east at 45 mph.

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

  SOURCE...Trained weather spotters reported quarter sized hail near 
           Avoca MN.

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

* Locations impacted include...
  Windom, Slayton, Mountain Lake, Fulda, Westbrook, Jeffers, Currie,
  Storden, Bingham Lake, Dovray, Avoca, Iona and Delft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4385 9595 4402 9581 4408 9562 4420 9538
      4419 9510 4411 9510 4410 9486 4385 9486
TIME...MOT...LOC 1359Z 248DEG 40KT 4413 9512 4401 9532 4393 9554 

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

$$

BP

2 follow-up statements

621 
WWUS53 KFSD 241432
SVSFSD

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

MNC033-101-241500-
/O.CON.KFSD.SV.W.0100.000000T0000Z-210824T1500Z/
Murray MN-Cottonwood MN-
932 AM CDT Tue Aug 24 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 AM CDT
FOR SOUTHEASTERN MURRAY AND COTTONWOOD COUNTIES...

At 931 AM CDT, severe thunderstorms were located along a line
extending from near Comfrey to near Windom to near Heron Lake, moving
east at 25 mph.

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

SOURCE...Trained weather spotters reported dime to quarter sized 
         hail and estimated wind gusts up to 60 mph near Westbrook 
         around 915 AM.

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

Locations impacted include...
Windom, Mountain Lake, Fulda, Westbrook, Jeffers, Storden, Bingham
Lake, Dovray, Avoca and Delft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4385 9579 4399 9569 4420 9525 4419 9510
      4411 9510 4410 9486 4385 9486
TIME...MOT...LOC 1431Z 259DEG 20KT 4407 9495 4395 9515 4387 9537 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.00 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH

$$

BP

634 
WWUS53 KFSD 241447
SVSFSD

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

MNC101-241456-
/O.CAN.KFSD.SV.W.0100.000000T0000Z-210824T1500Z/
Murray MN-
947 AM CDT Tue Aug 24 2021

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

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

LAT...LON 4385 9546 4392 9546 4396 9542 4411 9510
      4410 9486 4385 9486
TIME...MOT...LOC 1446Z 240DEG 34KT 4407 9485 4395 9505 4387 9527 

$$

MNC033-241500-
/O.CON.KFSD.SV.W.0100.000000T0000Z-210824T1500Z/
Cottonwood MN-
947 AM CDT Tue Aug 24 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 AM CDT
FOR COTTONWOOD COUNTY...

At 946 AM CDT, severe thunderstorms were located along a line
extending from near Comfrey to near Bingham Lake to 6 miles northeast
of Heron Lake, moving northeast at 40 mph.

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

SOURCE...Trained weather spotters reported dime to quarter sized 
         hail and 60 mph winds near Westbrook at 915 AM.

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

Locations impacted include...
  Mountain Lake and Windom.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4385 9546 4392 9546 4396 9542 4411 9510
      4410 9486 4385 9486
TIME...MOT...LOC 1446Z 240DEG 34KT 4407 9485 4395 9505 4387 9527 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.00 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH

$$

BP

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 24, 8:16 AM CDT	Severe Thunderstorm Warning	FSD	Cottonwood, Murray	44 min
Aug 24, 9:43 AM CDT	Severe Thunderstorm Warning	FSD	Nobles	47 min
Aug 24, 10:00 AM CDT	Severe Thunderstorm Warning	FSD	Cottonwood, Jackson, Nobles, Rock	45 min
Aug 24, 10:44 AM CDT	Severe Thunderstorm Warning	FSD	Jackson, Nobles	30 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2021 Every 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.