Alert archive / Minnesota / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 21, NWS Twin Cities, MN

May 10, 2011Benton County, Mille Lacs County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at May 10, 2011, 7:47 PM CDT for Benton County, Mille Lacs County, Minnesota. It was in force for 58 min. 3 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
May 10, 2011, 7:47 PM CDT (00:47 UTC)
Expired
May 10, 2011, 8:45 PM CDT
In force
58 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.75 in
Wind
60.0 mph

Counties Benton County, MN, Mille Lacs County, MN

The radar

The Minneapolis radar (KMPX), 97 km from the middle of the area, began a volume at 00:47 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
May 10, 7:58 PM CDTHAIL 2Ronneby, MN
May 10, 8:34 PM CDTHAIL 24 Ssw Foreston, MN
May 10, 8:37 PM CDTHAIL 1.751 E Pease, MNAT INTERSECTION OF 100TH ST AND 125TH AVE.

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
May 10, 5:53 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 0.8 hours before the alert went out and 96 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 2011-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4330 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 00:00Z on 2011-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 183 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
4330 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
1463 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
183 m²/s²
0-3 km storm-relative helicity
292 m²/s²
Significant tornado parameter
3.0
Supercell composite
33.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

513 
WUUS53 KMPX 110047
SVRMPX
MNC009-095-110145-
/O.NEW.KMPX.SV.W.0021.110511T0047Z-110511T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
747 PM CDT TUE MAY 10 2011

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN BENTON COUNTY IN CENTRAL MINNESOTA...
  SOUTHERN MILLE LACS COUNTY IN EAST CENTRAL MINNESOTA...

* UNTIL 845 PM CDT

* AT 742 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE    
  OF PRODUCING LARGE DAMAGING HAIL UP TO TENNIS BALL SIZE AND        
  DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR    
  RONNEBY...OR ABOUT 12 MILES SOUTHWEST OF MILACA...AND MOVING EAST  
  AT 25 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  MILACA...
  GLENDORADO...
  FORESTON...
  PEASE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS SITUATION. IF YOU ARE IN THE PATH OF THIS
STORM...PREPARE IMMEDIATELY FOR DESTRUCTIVE HAIL...WHICH CAN
SIGNIFICANTLY DAMAGE WINDOWS...SIDING AND VEHICLES. DAMAGING WINDS
ARE ALSO EXPECTED...WHICH WILL UPROOT TREES AND DOWN POWER LINES.
SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM
WINDOWS.

DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

REPORT ANY SIGNIFICANT WIND OR HAIL DAMAGE TO THE NEAREST LAW
ENFORCEMENT AGENCY...FOR RELAY TO THE NATIONAL WEATHER SERVICE.

A TORNADO WATCH REMAINS IN EFFECT UNTIL MIDNIGHT CDT WEDNESDAY
MORNING FOR EAST CENTRAL MINNESOTA.

&&

LAT...LON 4582 9351 4556 9372 4556 9399 4581 9376
TIME...MOT...LOC 0047Z 251DEG 20KT 4569 9384
WIND...HAIL 60MPH 1.75IN

$$
1 follow-up statement
964 
WWUS53 KMPX 110116
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
816 PM CDT TUE MAY 10 2011

MNC009-095-110145-
/O.CON.KMPX.SV.W.0021.000000T0000Z-110511T0145Z/
MILLE LACS MN-BENTON MN-
816 PM CDT TUE MAY 10 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHEASTERN
BENTON AND SOUTHERN MILLE LACS COUNTIES UNTIL 845 PM CDT...

AT 814 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE 
THUNDERSTORM CAPABLE OF PRODUCING LARGE DESTRUCTIVE HAIL UP TO 
TENNIS BALL SIZE...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS 
STORM WAS LOCATED NEAR FORESTON...OR 6 MILES SOUTHWEST OF 
MILACA...MOVING EAST AT 15 MPH.

LOCATIONS IMPACTED INCLUDE...
  MILACA...FORESTON...PEASE AND BOCK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS SITUATION. IF YOU ARE IN THE PATH OF THIS
STORM...PREPARE IMMEDIATELY FOR DESTRUCTIVE HAIL...WHICH CAN
SIGNIFICANTLY DAMAGE WINDOWS...SIDING AND VEHICLES. DAMAGING WINDS
ARE ALSO EXPECTED...WHICH CAN UPROOT TREES AND DOWN POWER LINES. SEEK
SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

&&

LAT...LON 4582 9351 4558 9370 4563 9388 4569 9387
      4581 9376
TIME...MOT...LOC 0116Z 252DEG 15KT 4571 9373
WIND...HAIL 60MPH 2.50IN

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 10, 7:00 PM CDTSevere Thunderstorm WarningMPXFreeborn, Steele60 min
May 10, 7:06 PM CDTSevere Thunderstorm WarningMPXBenton, Mille Lacs, Sherburne39 min
May 10, 7:21 PM CDTSevere Thunderstorm WarningMPXBenton, Morrison54 min
May 10, 7:24 PM CDTSevere Thunderstorm WarningMPXCarver, Dakota, Hennepin, Scott66 min
May 10, 7:43 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin, Isanti, Mille Lacs, Sherburne, Wright62 min
May 10, 7:46 PM CDTSevere Thunderstorm WarningMPXCarver, Hennepin, Scott59 min
May 10, 7:54 PM CDTSevere Thunderstorm WarningMPXDakota, Rice, Scott53 min
May 10, 7:55 PM CDTTornado WarningMPXAnoka, Hennepin, Sherburne, Wright35 min
May 10, 8:10 PM CDTTornado WarningMPXHennepin35 min
May 10, 8:27 PM CDTSevere Thunderstorm WarningMPXIsanti, Kanabec, Mille Lacs63 min
May 10, 8:44 PM CDTTornado WarningMPXAnoka, Isanti, Sherburne35 min
May 10, 8:51 PM CDTTornado WarningMPXIsanti, Kanabec, Mille Lacs39 min
May 10, 9:19 PM CDTSevere Thunderstorm WarningMPXKanabec41 min
May 10, 9:29 PM CDTSevere Thunderstorm WarningMPXIsanti, Kanabec, Mille Lacs46 min
May 10, 9:31 PM CDTAreal Flood AdvisoryMPXIsanti, Kanabec, Mille Lacs3 hr
May 10, 10:00 PM CDTSevere Thunderstorm WarningMPXIsanti43 min
May 10, 10:03 PM CDTSevere Thunderstorm WarningMPXKanabec36 min
May 10, 10:19 PM CDTSevere Thunderstorm WarningMPXChisago56 min
May 10, 10:43 PM CDTSevere Thunderstorm WarningMPXChisago47 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2011Every severe thunderstorm warning in 2011

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.