Alert archive / Minnesota / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 242, NWS Twin Cities, MN

August 1, 2012Dakota County, Goodhue County, Rice County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 1, 2012, 9:19 PM CDT for Dakota County, Goodhue County, Rice County, Minnesota. It was in force for 41 min. 5 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
Aug 1, 2012, 9:19 PM CDT (02:19 UTC)
Expired
Aug 1, 2012, 10:00 PM CDT
In force
41 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Dakota County, MN, Goodhue County, MN, Rice County, MN

The radar

The Minneapolis radar (KMPX), 68 km from the middle of the area, began a volume at 02:20 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
Aug 1, 9:19 PM CDTTSTM WND GST 48Cannon Falls, MNMNDOT ROAD SENSOR US-52 MILE POST 90.
Aug 1, 9:24 PM CDTTSTM WND DMGNorthfield, MN50 FT LONG LARGE TREE LIMB DOWN AND OTHER DEBRIS.
Aug 1, 9:30 PM CDTHAIL 11 Ssw Northfield, MNTIME ESTIMATED
Aug 1, 9:34 PM CDTTSTM WND DMG1 Ne Dundas, MNLARGE TREE DOWN.
Aug 1, 10:10 PM CDTHAIL 0.75Zumbrota, MNDIME SIZED HAIL. ESTIMATED 50 MPH WINDS WITH SOME BRANCHES DOWN. TIME ESTIMATED.

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
Aug 1, 5:12 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 2.3 hours before the alert went out and 71 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 2012-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2247 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 2012-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 square meters per square second.19395878Sfc1 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
2247 J/kg
Mixed-layer CIN
-65 J/kg
Mixed-layer LCL
1724 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.9

Open this sounding in Storm Lab

The text

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

728 
WUUS53 KMPX 020219
SVRMPX
MNC037-049-131-020300-
/O.NEW.KMPX.SV.W.0242.120802T0219Z-120802T0300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
919 PM CDT WED AUG 1 2012

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN DAKOTA COUNTY IN EAST CENTRAL MINNESOTA...
  WESTERN GOODHUE COUNTY IN SOUTHEAST MINNESOTA...
  RICE COUNTY IN SOUTH CENTRAL MINNESOTA...

* UNTIL 1000 PM CDT

* AT 915 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS OF 60 MPH. THIS
  STORM WAS LOCATED NEAR DUNDAS...OR ABOUT 10 MILES NORTH OF
  FARIBAULT...AND MOVING EAST AT 30 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  FARIBAULT...
  DUNDAS...
  NORTHFIELD...
  RUSKIN...
  NERSTRAND...
  STANTON...
  DENNISON...
  KENYON...
  CANNON FALLS...
  BOMBAY...
  WASTEDO...
  HADER...
  WANAMINGO...
  ZUMBROTA...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR
DAMAGING WINDS IN EXCESS OF 60 MPH AND LARGE HAIL. SEEK SHELTER NOW
INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 4457 9263 4422 9264 4428 9343 4456 9326
TIME...MOT...LOC 0219Z 280DEG 27KT 4444 9323
WIND...HAIL 60MPH 1.00IN

$$
2 follow-up statements
751 
WWUS53 KMPX 020236
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
936 PM CDT WED AUG 1 2012

MNC037-049-131-020300-
/O.CON.KMPX.SV.W.0242.000000T0000Z-120802T0300Z/
DAKOTA MN-GOODHUE MN-RICE MN-
936 PM CDT WED AUG 1 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR EASTERN
RICE...CENTRAL GOODHUE AND SOUTHEASTERN DAKOTA COUNTIES UNTIL 1000 PM
CDT...

AT 933 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A LINE OF
SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS OF 60 MPH. 
THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM RANDOLPH TO
DENNISON TO NERSTRAND...MOVING EAST AT 30 MPH. NICKEL SIZE HAIL MAY
ALSO ACCOMPANY THESE DAMAGING WINDS.

LOCATIONS IMPACTED INCLUDE...
  DENNISON...KENYON...CANNON FALLS...BOMBAY...WASTEDO...HADER...
  WANAMINGO...WELCH AND ZUMBROTA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...HAIL...AND DEADLY LIGHTNING. FOR YOUR PROTECTION MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS.

&&

LAT...LON 4427 9324 4456 9313 4457 9263 4422 9264
TIME...MOT...LOC 0237Z 280DEG 27KT 4453 9301 4442 9304
          4429 9305
WIND...HAIL 60MPH 0.88IN

$$

LS
525 
WWUS53 KMPX 020301
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1001 PM CDT WED AUG 1 2012

MNC037-049-131-020316-
/O.EXP.KMPX.SV.W.0242.000000T0000Z-120802T0300Z/
DAKOTA MN-GOODHUE MN-RICE MN-
1001 PM CDT WED AUG 1 2012

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN RICE...CENTRAL GOODHUE
AND SOUTHEASTERN DAKOTA COUNTIES HAS EXPIRED...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAVE WEAKENED BELOW
SEVERE LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR
PROPERTY.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1 AM CDT.

LAT...LON 4427 9324 4456 9313 4457 9263 4422 9264
TIME...MOT...LOC 0236Z 280DEG 27KT 4450 9302 4439 9306
          4426 9307

$$

JRB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 7:08 PM CDTSevere Thunderstorm WarningMPXMcLeod, Renville, Sibley37 min
Aug 1, 7:44 PM CDTSpecial Weather StatementMPXBlue Earth, Nicollet, Sibley, Watonwan61 min
Aug 1, 8:48 PM CDTSevere Thunderstorm WarningMPXCarver, Hennepin, Scott20 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2012Every severe thunderstorm warning in 2012

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.