Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 112, NWS Twin Cities, MN

August 28, 20215 counties in Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 28, 2021, 7:13 PM CDT for 5 counties in Minnesota. It was in force for 32 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 28, 2021, 7:13 PM CDT (00:13 UTC)
Expired: Aug 28, 2021, 7:45 PM CDT
In force: 32 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Blue Earth County, MN, Le Sueur County, MN, Nicollet County, MN, Rice County, MN, Sibley County, MN

The radar

The Minneapolis radar (KMPX), 61 km from the middle of the area, began a volume at 00:13 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 28, 7:20 PM CDT	TSTM WND DMG	1 Ssw Le Sueur, MN	A NUMBER OF LARGE LIMBS WERE BLOWN DOWN IN LE SUEUR, INCLUDING ONE THAT WAS 12 INCHES IN DIAMETER.

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.

Issued	Product	Office	Lasted
Aug 28, 5:59 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 0.2 hours before the alert went out and 61 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: 1990 J/kg
Mixed-layer CIN: -120 J/kg
Mixed-layer LCL: 977 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 252 m²/s²
0-3 km storm-relative helicity: 227 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 5.0

Open this sounding in Storm Lab

The text

As transmitted.

211 
WUUS53 KMPX 290013
SVRMPX
MNC013-079-103-131-143-290045-
/O.NEW.KMPX.SV.W.0112.210829T0013Z-210829T0045Z/

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

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Le Sueur County in south central Minnesota...
  Southeastern Sibley County in central Minnesota...
  Northeastern Blue Earth County in south central Minnesota...
  Western Rice County in south central Minnesota...
  Eastern Nicollet County in south central Minnesota...

* Until 745 PM CDT.

* At 713 PM CDT, severe thunderstorms were located along a line
  extending from 7 miles northwest of St. Peter to near Mankato,
  moving northeast at 60 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Severe thunderstorms will be near...
  Le Sueur around 720 PM CDT.
  Madison Lake and Henderson around 725 PM CDT.
  Elysian and Cleveland around 730 PM CDT.

Other locations in the path of these severe thunderstorms include
Montgomery, Waterville, New Prague, Faribault, Morristown and Warsaw.

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 4445 9418 4455 9382 4455 9351 4421 9331
      4419 9345 4420 9376 4415 9377 4411 9406
TIME...MOT...LOC 0013Z 245DEG 52KT 4441 9407 4413 9405 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

NDC

2 follow-up statements

703 
WWUS53 KMPX 290029
SVSMPX

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

MNC013-079-103-131-143-290045-
/O.CON.KMPX.SV.W.0112.000000T0000Z-210829T0045Z/
Le Sueur MN-Sibley MN-Blue Earth MN-Rice MN-Nicollet MN-
729 PM CDT Sat Aug 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM CDT
FOR LE SUEUR...SOUTHEASTERN SIBLEY...NORTHEASTERN BLUE EARTH...
WESTERN RICE AND NORTHEASTERN NICOLLET COUNTIES...

At 729 PM CDT, severe thunderstorms were located along a line
extending from 5 miles east of Henderson to near Madison Lake, moving
northeast at 60 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
  Montgomery, New Prague, Waterville, Morristown, Warsaw and 
  Faribault.

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 4455 9382 4455 9351 4421 9331 4419 9345
      4420 9376 4422 9406 4451 9398
TIME...MOT...LOC 0029Z 245DEG 52KT 4450 9379 4422 9377 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

NDC

201 
WWUS53 KMPX 290036
SVSMPX

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

MNC013-079-103-131-143-290046-
/O.EXP.KMPX.SV.W.0112.000000T0000Z-210829T0045Z/
Le Sueur MN-Sibley MN-Blue Earth MN-Rice MN-Nicollet MN-
736 PM CDT Sat Aug 28 2021

...THE SEVERE THUNDERSTORM WARNING FOR LE SUEUR...SOUTHEASTERN
SIBLEY...NORTHEASTERN BLUE EARTH...WESTERN RICE AND NORTHEASTERN
NICOLLET COUNTIES WILL EXPIRE AT 745 PM CDT...

The storms which prompted the warning have weakened. Therefore, the 
warning will be allowed to expire.However gusty winds and heavy rain 
are still possible with these thunderstorms.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
south central, central and east central Minnesota.

LAT...LON 4455 9382 4455 9351 4421 9331 4419 9345
      4420 9376 4422 9406 4451 9398
TIME...MOT...LOC 0036Z 245DEG 52KT 4453 9369 4425 9367 

$$

NDC

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 28, 7:40 PM CDT	Severe Thunderstorm Warning	MPX	Brown, Redwood	23 min
Aug 28, 7:41 PM CDT	Special Weather Statement	MPX	Blue Earth, Le Sueur, Rice, Scott	34 min
Aug 28, 8:07 PM CDT	Special Weather Statement	MPX	Rice	23 min
Aug 28, 8:17 PM CDT	Special Weather Statement	MPX	Redwood	28 min
Aug 28, 8:26 PM CDT	Special Weather Statement	MPX	Dakota, Goodhue	34 min
Aug 28, 8:57 PM CDT	Special Weather Statement	MPX	Goodhue	33 min
Aug 28, 8:59 PM CDT	Special Weather Statement	MPX	Redwood	31 min
Aug 28, 9:02 PM CDT	Flash Flood Warning	MPX	Redwood	6 hr
Aug 28, 9:29 PM CDT	Special Weather Statement	MPX	Brown	31 min
Aug 28, 10:02 PM CDT	Special Weather Statement	MPX	Brown	43 min
Aug 28, 10:15 PM CDT	Tornado Warning	MPX	Brown	30 min
Aug 28, 10:52 PM CDT	Special Weather Statement	MPX	Nicollet	53 min
Aug 28, 11:28 PM CDT	Special Weather Statement	MPX	Le Sueur	47 min
Aug 29, 12:12 AM CDT	Special Weather Statement	MPX	Hennepin, Ramsey	93 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.