Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 129, NWS Twin Cities, MN

September 17, 20216 counties in Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Sep 17, 2021, 2:59 AM CDT for 6 counties in Minnesota. It was in force for 16 min. 14 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
Sep 17, 2021, 2:59 AM CDT (07:59 UTC)
Expired
Sep 17, 2021, 3:15 AM CDT
In force
16 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Anoka County, MN, Dakota County, MN, Hennepin County, MN, Ramsey County, MN, Scott County, MN, Washington County, MN

The radar

The Minneapolis radar (KMPX), 41 km from the middle of the area, began a volume at 08:02 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
Sep 17, 3:00 AM CDTTSTM WND DMGSavage, MNPHONED IN REPORT OF DAMAGE TO BUILDINGS AND POWER INFRASTRUCTURE, WITH LARGE AMOUNTS OF DEBRIS SCATTERED AROUND. LARGE PORTION OF CITY WITHOUT POWER. TIME ESTIMATED BY RADAR.
Sep 17, 3:00 AM CDTTORNADO1 W Savage, MNA TORNADO TOUCHED DOWN NEAR HIGHWAY 13 AND CONNELLY PKWY AND MOVED EAST FOR 2.1 MILES. MAX WINDS ESTIMATED AT 85 MPH. RATED EF0. MOST DAMAGE WAS DUE TO TREES FALLING ON HOUSES AND VEHICLES. ROOF DAMAGE OCCURRED AT SAVAGE PUBLIC WORKS AND A LIGHT STANDARD WAS B
Sep 17, 3:04 AM CDTTSTM WND DMGBloomington, MNLARGE TREE, GREATER THAN 1 FOOT IN DIAMETER, DOWN. TIME ESTIMATED FROM RADAR.
Sep 17, 3:06 AM CDTTSTM WND DMG1 S Burnsville, MNTIME ESTIMATED FROM RADAR. MULTIPLE TREES UPROOTED.
Sep 17, 3:06 AM CDTTSTM WND DMG4 Ne Burnsville, MNTIME ESTIMATED. MULTIPLE TREES DOWN.
Sep 17, 3:06 AM CDTTSTM WND DMGBurnsville, MNTIME ESTIMATED FROM RADAR. LARGE TREE UPROOTED.
Sep 17, 3:06 AM CDTTSTM WND DMGRichfield, MNMULTIPLE TREES DOWN/UPROOTED IN RICHFIELD. TIME ESTIMATED.
Sep 17, 3:08 AM CDTTSTM WND DMG4 S Eagan, MN4-6 INCH TREE LIMBS DOWN OVER ROADWAYS. PICTURE VIA TWITTER. TIME ESTIMATED VIA RADAR.
Sep 17, 3:08 AM CDTTORNADO3 Ne Burnsville, MNA TORNADO TOUCHED DOWN NEAR HIGHWAY 13 AND CLIFF RD IN NORTHEAST BURNSVILLE. IT WAS ON THE GROUND FOR 1 MILE AND WAS RATED EF0. MOST DAMAGE WAS DUE TO TREES FALLING ON HOUSES AND VEHICLES.
Sep 17, 3:09 AM CDTTSTM WND GST 643 E Richfield, MN64MPH WIND GUST MEASURED AT MSP INTERNATIONAL AIRPORT.
Sep 17, 3:11 AM CDTTSTM WND DMGEagan, MNMULTIPLE TREES DOWN/UPROOTED IN EAGAN. TIME ESTIMATED FROM RADAR.
Sep 17, 3:13 AM CDTTSTM WND DMG4 Nnw Rosemount, MN3 LARGE TREES UPROOTED. TIME ESTIMATED FROM RADAR.
Sep 17, 3:13 AM CDTTSTM WND DMG4 S Eagan, MNTIME ESTIMATED FROM RADAR. NUMEROUS LARGE TREES DOWN. ONE ON THE FRONT OF A HOUSE AND ONE ON TOP OF TWO CARS.
Sep 17, 3:15 AM CDTTSTM WND DMG1 S Savage, MNSMALL TREE LIMBS DOWN, HOME WEATHER STATION RECORDED 58MPH GUST.

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

The nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 8.0 hours before the alert went out and 397 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, International Fa, MN at 00:00Z on 2021-09-17Temperature 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, International Fa, MN at 00:00Z on 2021-09-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -33 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
832 m above ground
0-6 km bulk shear
75 kt
0-1 km storm-relative helicity
-33 m²/s²
0-3 km storm-relative helicity
175 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

592 
WUUS53 KMPX 170759
SVRMPX
MNC003-037-053-123-139-163-170815-
/O.NEW.KMPX.SV.W.0129.210917T0759Z-210917T0815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
259 AM CDT Fri Sep 17 2021

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Eastern Hennepin County in east central Minnesota...
  Northwestern Dakota County in east central Minnesota...
  Northeastern Scott County in east central Minnesota...
  Southeastern Anoka County in east central Minnesota...
  Western Washington County in east central Minnesota...
  Ramsey County in east central Minnesota...

* Until 315 AM CDT.

* At 259 AM CDT, severe thunderstorms were located along a line
  extending from Brooklyn Park to Shakopee, moving northeast at 60
  mph.

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

  SOURCE...Radar indicated.

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

* Severe thunderstorms will be near...
  Minneapolis, Brooklyn Park, Coon Rapids, Roseville and Brooklyn 
  Center around 305 AM CDT.
  Apple Valley, Shoreview, New Brighton, Arden Hills and MSP 
  International Airport around 310 AM CDT.
  Bloomington, Eagan, Blaine, Inver Grove Heights and Rosemount 
  around 315 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4481 9290 4467 9352 4514 9342 4530 9295
      4529 9288
TIME...MOT...LOC 0759Z 245DEG 51KT 4509 9337 4476 9345 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

TDH
1 follow-up statement
991 
WWUS53 KMPX 170808
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
308 AM CDT Fri Sep 17 2021

MNC139-170818-
/O.CAN.KMPX.SV.W.0129.000000T0000Z-210917T0815Z/
Scott MN-
308 AM CDT Fri Sep 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN SCOTT COUNTY IS
CANCELLED...

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

LAT...LON 4472 9328 4522 9319 4530 9295 4529 9288
      4481 9290
TIME...MOT...LOC 0808Z 247DEG 57KT 4513 9319 4481 9326 

$$

MNC003-037-053-123-163-170815-
/O.CON.KMPX.SV.W.0129.000000T0000Z-210917T0815Z/
Hennepin MN-Dakota MN-Anoka MN-Washington MN-Ramsey MN-
308 AM CDT Fri Sep 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 AM CDT
FOR SOUTHEASTERN HENNEPIN...NORTHWESTERN DAKOTA...EAST CENTRAL
ANOKA...WESTERN WASHINGTON AND RAMSEY COUNTIES...

At 308 AM CDT, severe thunderstorms were located along a line
extending from near Mounds View to near Burnsville, moving northeast
at 65 mph.

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

SOURCE...Radar indicated.

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

These severe storms will be near...
  Lino Lakes, Hugo, Vadnais Heights and Mahtomedi around 315 AM CDT.

Other locations in the path of these severe thunderstorms include
Cottage Grove, Forest Lake, St. Paul Park, Woodbury and Lake Elmo.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4472 9328 4522 9319 4530 9295 4529 9288
      4481 9290
TIME...MOT...LOC 0808Z 247DEG 57KT 4513 9319 4481 9326 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

TDH

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 16, 7:07 PM CDTTornado WarningMPXMille Lacs, Morrison23 min
Sep 16, 7:08 PM CDTSevere Thunderstorm WarningMPXChippewa, Kandiyohi37 min
Sep 16, 7:14 PM CDTSpecial Weather StatementMPXChippewa31 min
Sep 16, 7:18 PM CDTSevere Thunderstorm WarningMPXChippewa, Kandiyohi, Renville27 min
Sep 16, 7:30 PM CDTSevere Thunderstorm WarningMPXKanabec, Mille Lacs, Morrison45 min
Sep 16, 7:43 PM CDTSpecial Weather StatementMPXMille Lacs47 min
Sep 16, 7:44 PM CDTSevere Thunderstorm Warning Considerable damage threatMPXKandiyohi, Renville31 min
Sep 16, 7:47 PM CDTSpecial Weather StatementMPXMeeker28 min
Sep 16, 7:53 PM CDTSevere Thunderstorm WarningMPXMille Lacs37 min
Sep 16, 8:12 PM CDTSevere Thunderstorm WarningMPXKandiyohi, McLeod, Meeker, Renville33 min
Sep 16, 8:38 PM CDTSpecial Weather StatementMPXIsanti37 min
Sep 16, 8:45 PM CDTSevere Thunderstorm WarningMPXMcLeod, Meeker, Wright30 min
Sep 16, 9:12 PM CDTSpecial Weather StatementMPXHennepin33 min
Sep 16, 10:24 PM CDTSpecial Weather StatementMPXLac qui Parle36 min
Sep 16, 10:37 PM CDTSpecial Weather StatementMPXKanabec23 min
Sep 16, 11:06 PM CDTSpecial Weather StatementMPXStearns24 min
Sep 17, 12:09 AM CDTSpecial Weather StatementMPXMille Lacs36 min
Sep 17, 12:21 AM CDTSpecial Weather StatementMPXBenton24 min
Sep 17, 12:47 AM CDTSpecial Weather StatementMPXMille Lacs28 min
Sep 17, 12:55 AM CDTSpecial Weather StatementMPXRedwood, Yellow Medicine35 min
Sep 17, 1:10 AM CDTSpecial Weather StatementMPXKanabec20 min
Sep 17, 1:20 AM CDTSpecial Weather StatementMPXBenton25 min
Sep 17, 1:29 AM CDTSevere Thunderstorm WarningMPXBrown, Redwood, Renville31 min
Sep 17, 1:48 AM CDTSpecial Weather StatementMPXKanabec, Mille Lacs27 min
Sep 17, 1:53 AM CDTSpecial Weather StatementMPXMcLeod, Sibley37 min
Sep 17, 2:00 AM CDTSpecial Weather StatementMPXBrown, Nicollet30 min
Sep 17, 2:29 AM CDTSevere Thunderstorm WarningMPXCarver, McLeod, Scott, Sibley16 min
Sep 17, 2:34 AM CDTSpecial Weather StatementMPXLe Sueur, Rice26 min
Sep 17, 2:45 AM CDTSevere Thunderstorm WarningMPXCarver, Hennepin, Scott15 min
Sep 17, 3:15 AM CDTSevere Thunderstorm Warning Considerable damage threatMPXWashington15 min
Sep 17, 3:18 AM CDTSpecial Weather StatementMPXGoodhue27 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.