Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 109, NWS Twin Cities, MN

August 28, 2021Brown County, Redwood County, Watonwan County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 28, 2021, 6:06 PM CDT for Brown County, Redwood County, Watonwan County, Minnesota. It was in force for 54 min. 6 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 28, 2021, 6:06 PM CDT (23:06 UTC)
Expired
Aug 28, 2021, 7:00 PM CDT
In force
54 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Tornado
Possible
Damage threat
Considerable
Hail
0.75 in
Wind
70.0 mph

Counties Brown County, MN, Redwood County, MN, Watonwan County, MN

The radar

The Minneapolis radar (KMPX), 121 km from the middle of the area, began a volume at 23:06 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 28, 6:20 PM CDTTSTM WND DMG4 N Comfrey, MNLARGE TREE SNAPPED AND SMALLER TREES DOWN. PICS SENT VIA TWITTER.
Aug 28, 6:20 PM CDTTSTM WND DMGComfrey, MNLARGE TREE UPROOTED. PIC SENT VIA TWITTER.
Aug 28, 6:30 PM CDTTSTM WND DMG6 Nnw Sveadahl, MNLARGE TREE DOWN.
Aug 28, 6:46 PM CDTTSTM WND DMGSleepy Eye, MNWIND DAMAGE/TREES DOWN SOUTH PART OF SLEEPY EYE.
Aug 28, 6:50 PM CDTTSTM WND DMGSveadahl, MNTREES DOWN IN SVEADAHL.
Aug 28, 6:58 PM CDTTSTM WND DMGComfrey, MNREPORT FROM MPING: 1-INCH TREE LIMBS BROKEN; SHINGLES BLOWN OFF.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 28, 5:59 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.1 hours before the alert went out and 118 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 2021-08-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1550 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 2021-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 139 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
1550 J/kg
Mixed-layer CIN
-130 J/kg
Mixed-layer LCL
676 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
139 m²/s²
0-3 km storm-relative helicity
193 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.3

Open this sounding in Storm Lab

The text

As transmitted.

761 
WUUS53 KMPX 282306
SVRMPX
MNC015-127-165-290000-
/O.NEW.KMPX.SV.W.0109.210828T2306Z-210829T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
606 PM CDT Sat Aug 28 2021

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Redwood County in southwestern Minnesota...
  Brown County in south central Minnesota...
  Northwestern Watonwan County in south central Minnesota...

* Until 700 PM CDT.

* At 605 PM CDT, severe thunderstorms were located along a line
  extending from near Tracy to 6 miles southeast of Storden, moving
  northeast at 55 mph.

  HAZARD...70 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Severe thunderstorms will be near...
  Wabasso around 625 PM CDT.

Other locations in the path of these severe thunderstorms include
Comfrey, Redwood Falls, Morgan, Franklin, Morton, Hanska and New Ulm.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 4411 9486 4411 9509 4419 9510 4420 9560
      4435 9559 4459 9511 4452 9488 4445 9478
      4443 9470 4439 9467 4435 9449 4427 9442
      4426 9437 4412 9437 4397 9486
TIME...MOT...LOC 2305Z 245DEG 48KT 4428 9557 4395 9525 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

NDC
1 follow-up statement
619 
WWUS53 KMPX 282331
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
631 PM CDT Sat Aug 28 2021

MNC015-127-165-290000-
/O.CON.KMPX.SV.W.0109.000000T0000Z-210829T0000Z/
Redwood MN-Brown MN-Watonwan MN-
631 PM CDT Sat Aug 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM CDT
FOR REDWOOD...BROWN AND NORTHWESTERN WATONWAN COUNTIES...

At 630 PM CDT, severe thunderstorms were located along a line
extending from near Wabasso to near Comfrey, moving east at 55 mph.

HAZARD...70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
  Comfrey, Morgan, Franklin, Hanska and New Ulm.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 4411 9486 4411 9509 4419 9510 4420 9546
      4440 9550 4459 9511 4452 9488 4445 9478
      4443 9470 4439 9467 4435 9449 4427 9442
      4426 9437 4412 9437 4397 9486
TIME...MOT...LOC 2330Z 270DEG 48KT 4441 9518 4408 9486 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

NDC

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 27, 8:21 PM CDTFlash Flood WarningMPXFreeborn4 hr
Aug 27, 11:48 PM CDTSpecial Weather StatementMPXFreeborn87 min
Aug 28, 8:14 AM CDTSpecial Weather StatementMPXStevens61 min
Aug 28, 9:27 AM CDTSevere Thunderstorm Warning Considerable damage threatMPXLac qui Parle33 min
Aug 28, 9:49 AM CDTSevere Thunderstorm WarningMPXDouglas, Pope, Stevens56 min
Aug 28, 9:54 AM CDTSevere Thunderstorm WarningMPXSwift51 min
Aug 28, 10:31 AM CDTSevere Thunderstorm Warning Destructive damage threatMPXSwift44 min
Aug 28, 10:41 AM CDTSevere Thunderstorm WarningMPXDouglas, Pope, Stearns, Todd49 min
Aug 28, 10:53 AM CDTSevere Thunderstorm WarningMPXKandiyohi52 min
Aug 28, 11:20 AM CDTSevere Thunderstorm Warning Considerable damage threatMPXStearns40 min
Aug 28, 11:24 AM CDTTornado WarningMPXStearns36 min
Aug 28, 11:32 AM CDTSevere Thunderstorm Warning Considerable damage threatMPXMorrison, Todd43 min
Aug 28, 11:45 AM CDTSevere Thunderstorm Warning Considerable damage threatMPXBenton, Mille Lacs, Morrison, Sherburne45 min
Aug 28, 12:04 PM CDTTornado WarningMPXBenton, Mille Lacs41 min
Aug 28, 12:27 PM CDTSevere Thunderstorm Warning Considerable damage threatMPXIsanti, Kanabec, Mille Lacs48 min
Aug 28, 12:43 PM CDTSpecial Weather StatementMPXAnoka47 min
Aug 28, 1:07 PM CDTSpecial Weather StatementMPXChisago23 min
Aug 28, 1:29 PM CDTSevere Thunderstorm WarningMPXChisago, Isanti46 min
Aug 28, 6:19 PM CDTTornado WarningMPXBrown, Redwood26 min
Aug 28, 6:26 PM CDTSevere Thunderstorm Warning Considerable damage threatMPXBlue Earth, Faribault, Martin, Watonwan64 min
Aug 28, 6:43 PM CDTSevere Thunderstorm WarningMPXBlue Earth, Brown, Nicollet, Redwood, Renville, Sibley and 1 more62 min
Aug 28, 6:51 PM CDTTornado WarningMPXBrown, Nicollet24 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.