Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 97, NWS Twin Cities, MN

August 26, 2021Pierce County, Saint Croix County, Wisconsin; Washington County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 26, 2021, 2:44 PM CDT for Pierce County, Saint Croix County, Wisconsin; Washington County, Minnesota. It was in force for 46 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 26, 2021, 2:44 PM CDT (19:44 UTC)
Expired
Aug 26, 2021, 3:30 PM CDT
In force
46 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Washington County, MN, Pierce County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 58 km from the middle of the area, began a volume at 19:46 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.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 7.7 hours before the alert went out and 60 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 2021-08-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-08-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1566 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
146 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

173 
WUUS53 KMPX 261944
SVRMPX
MNC163-WIC093-109-262030-
/O.NEW.KMPX.SV.W.0097.210826T1944Z-210826T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
244 PM CDT Thu Aug 26 2021

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Southern Washington County in east central Minnesota...
  Northwestern Pierce County in west central Wisconsin...
  Southwestern St. Croix County in west central Wisconsin...

* Until 330 PM CDT.

* At 243 PM CDT, a severe thunderstorm was located near Cottage
  Grove, or 12 miles west of River Falls, moving east at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  River Falls, Woodbury, Maplewood, Cottage Grove, Inver Grove
  Heights, Oakdale, Hastings, Rosemount, South St. Paul, Hudson, Lake
  Elmo and St. Paul Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4474 9280 4475 9282 4475 9285 4477 9288
      4478 9294 4477 9297 4477 9301 4489 9302
      4489 9299 4497 9299 4509 9246 4475 9234
TIME...MOT...LOC 1943Z 253DEG 35KT 4484 9287 

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

$$

PEM
2 follow-up statements
755 
WWUS53 KMPX 262005
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
305 PM CDT Thu Aug 26 2021

MNC163-262015-
/O.CAN.KMPX.SV.W.0097.000000T0000Z-210826T2030Z/
Washington MN-
305 PM CDT Thu Aug 26 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN WASHINGTON 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 4474 9280 4477 9281 4482 9277 4490 9278
      4491 9276 4494 9275 4497 9277 4502 9276
      4509 9246 4475 9234
TIME...MOT...LOC 2005Z 253DEG 35KT 4490 9258 

$$

WIC093-109-262030-
/O.CON.KMPX.SV.W.0097.000000T0000Z-210826T2030Z/
Pierce WI-St. Croix WI-
305 PM CDT Thu Aug 26 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM CDT
FOR NORTHWESTERN PIERCE AND SOUTHWESTERN ST. CROIX COUNTIES...

At 305 PM CDT, a severe thunderstorm was located near River Falls,
moving east at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
River Falls, Hudson, Prescott, North Hudson, Ellsworth, Afton,
Hammond, Baldwin, Roberts, Lakeland, Martel and Willow River State
Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4474 9280 4477 9281 4482 9277 4490 9278
      4491 9276 4494 9275 4497 9277 4502 9276
      4509 9246 4475 9234
TIME...MOT...LOC 2005Z 253DEG 35KT 4490 9258 

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

$$

PEM
128 
WWUS53 KMPX 262022
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
322 PM CDT Thu Aug 26 2021

WIC093-109-262032-
/O.EXP.KMPX.SV.W.0097.000000T0000Z-210826T2030Z/
Pierce WI-St. Croix WI-
322 PM CDT Thu Aug 26 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN PIERCE AND
SOUTHWESTERN ST. CROIX COUNTIES WILL EXPIRE AT 330 PM CDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with this thunderstorm.

LAT...LON 4474 9280 4477 9281 4482 9277 4490 9278
      4491 9276 4494 9275 4497 9277 4502 9276
      4509 9246 4475 9234
TIME...MOT...LOC 2022Z 253DEG 35KT 4494 9238 

$$

PEM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 26, 3:21 PM CDTSpecial Weather StatementMPXDunn, Pierce, Saint Croix24 min
Aug 26, 3:47 PM CDTSpecial Weather StatementMPXChippewa, Dunn, Eau Claire58 min
Aug 26, 10:39 AM CDTSevere Thunderstorm WarningMPXLac qui Parle, Yellow Medicine51 min
Aug 26, 10:54 AM CDTSpecial Weather StatementMPXStevens36 min
Aug 26, 11:05 AM CDTSevere Thunderstorm WarningMPXChippewa, Swift40 min
Aug 26, 11:32 AM CDTSpecial Weather StatementMPXChippewa28 min
Aug 26, 11:37 AM CDTSevere Thunderstorm Warning Considerable damage threatMPXChippewa, Kandiyohi, Swift23 min
Aug 26, 12:08 PM CDTSpecial Weather StatementMPXKandiyohi, Meeker22 min
Aug 26, 12:22 PM CDTSpecial Weather StatementMPXRenville23 min
Aug 26, 12:25 PM CDTWind AdvisoryMPXBenton, Chippewa, Douglas, Kandiyohi, Lac qui Parle, Meeker and 9 more3 hr
Aug 26, 12:52 PM CDTSpecial Weather StatementMPXMcLeod23 min
Aug 26, 1:15 PM CDTSpecial Weather StatementMPXCarver30 min
Aug 26, 1:44 PM CDTSpecial Weather StatementMPXCarver, Hennepin31 min
Aug 26, 1:47 PM CDTSevere Thunderstorm WarningMPXCarver, Hennepin28 min
Aug 26, 2:05 PM CDTSevere Thunderstorm WarningMPXDakota, Hennepin, Ramsey, Scott, Washington40 min
Aug 26, 2:14 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin, Ramsey46 min
Aug 26, 2:51 PM CDTSpecial Weather StatementMPXWashington24 min
Aug 26, 5:44 PM CDTFlash Flood WatchMPXAnoka, Benton, Blue Earth, Brown, Carver, Dakota and 22 more13 hr

Nearby

Severe Thunderstorm Warnings in Wisconsin, 2021Severe 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.