Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 71, NWS Twin Cities, MN

August 11, 2021Anoka County, Hennepin County, Ramsey County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 11, 2021, 6:45 AM CDT for Anoka County, Hennepin County, Ramsey County, Minnesota. It was in force for 30 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 11, 2021, 6:45 AM CDT (11:45 UTC)
Expired
Aug 11, 2021, 7:15 AM CDT
In force
30 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.25 in
Wind
50.0 mph

Counties Anoka County, MN, Hennepin County, MN, Ramsey County, MN

The radar

The Minneapolis radar (KMPX), 38 km from the middle of the area, began a volume at 11:45 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 00:00Z, 11.8 hours before the alert went out and 40 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 00:00Z on 2021-08-11Temperature 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 00:00Z on 2021-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1997 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

735 
WUUS53 KMPX 111145
SVRMPX
MNC003-053-123-111215-
/O.NEW.KMPX.SV.W.0071.210811T1145Z-210811T1215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
645 AM CDT Wed Aug 11 2021

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Central Hennepin County in east central Minnesota...
  Southeastern Anoka County in east central Minnesota...
  Ramsey County in east central Minnesota...

* Until 715 AM CDT.

* At 645 AM CDT, a severe thunderstorm was located over Plymouth, or
  11 miles west of Minneapolis, moving east at 50 mph.

  HAZARD...Half dollar size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* This severe thunderstorm will be near...
  St. Louis Park and Hopkins around 650 AM CDT.
  Minneapolis, Brooklyn Center and Golden Valley around 655 AM CDT.
  Fridley, Columbia Heights, Mounds View and Spring Lake Park around 
  700 AM CDT.
  Roseville, Shoreview, New Brighton and Arden Hills around 705 AM 
  CDT.

Other locations in the path of this severe thunderstorm include St.
Paul, West St. Paul, Vadnais Heights, Maplewood, White Bear Lake and
Mahtomedi.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and deadly cloud to ground
lightning. Seek shelter inside a well-built structure. Stay away from
windows.

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in the Twin Cities.

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 4513 9302 4512 9298 4489 9299 4490 9304
      4492 9305 4492 9313 4491 9314 4495 9361
      4509 9362 4520 9302
TIME...MOT...LOC 1145Z 267DEG 42KT 4501 9349 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

JPC
2 follow-up statements
532 
WWUS53 KMPX 111159
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
659 AM CDT Wed Aug 11 2021

MNC003-053-123-111215-
/O.CON.KMPX.SV.W.0071.000000T0000Z-210811T1215Z/
Hennepin MN-Anoka MN-Ramsey MN-
659 AM CDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 715 AM CDT
FOR EAST CENTRAL HENNEPIN...SOUTHEASTERN ANOKA AND RAMSEY COUNTIES...

At 658 AM CDT, a severe thunderstorm was located over Columbia
Heights, or near Minneapolis, moving east at 50 mph.

HAZARD...Half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

This severe storm will be near...
  Shoreview and West St. Paul around 705 AM CDT.

Other locations in the path of this severe thunderstorm include St.
Paul, Maplewood, Vadnais Heights, White Bear Lake and Mahtomedi.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and deadly cloud to ground
lightning. Seek shelter inside a well-built structure. Stay away from
windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
the Twin Cities.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 4513 9302 4512 9298 4489 9299 4490 9304
      4492 9305 4492 9313 4491 9314 4493 9335
      4512 9334 4520 9302
TIME...MOT...LOC 1158Z 265DEG 42KT 4501 9325 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

JPC
973 
WWUS53 KMPX 111212
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
712 AM CDT Wed Aug 11 2021

MNC003-053-123-111221-
/O.EXP.KMPX.SV.W.0071.000000T0000Z-210811T1215Z/
Hennepin MN-Anoka MN-Ramsey MN-
712 AM CDT Wed Aug 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL HENNEPIN...
SOUTHEASTERN ANOKA AND RAMSEY COUNTIES WILL EXPIRE AT 715 AM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
the Twin Cities.

LAT...LON 4513 9302 4512 9298 4489 9299 4490 9304
      4492 9305 4492 9313 4491 9314 4493 9335
      4512 9334 4520 9302
TIME...MOT...LOC 1211Z 267DEG 42KT 4502 9305 

$$

JPC

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 6:12 AM CDTSpecial Weather StatementMPXHennepin, Wright33 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.