Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 78, NWS Twin Cities, MN

May 19, 2012Polk County, Saint Croix County, Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at May 19, 2012, 7:42 PM CDT for Polk County, Saint Croix County, Wisconsin. It was in force for 63 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
May 19, 2012, 7:42 PM CDT (00:42 UTC)
Expired
May 19, 2012, 8:45 PM CDT
In force
63 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
0.88 in
Wind
60.0 mph

Counties Polk County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 91 km from the middle of the area, began a volume at 00:44 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, 0.7 hours before the alert went out and 93 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 2012-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1062 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 2012-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 139 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
1062 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
2089 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
139 m²/s²
0-3 km storm-relative helicity
188 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.6

Open this sounding in Storm Lab

The text

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

628 
WUUS53 KMPX 200042
SVRMPX
WIC095-109-200145-
/O.NEW.KMPX.SV.W.0078.120520T0042Z-120520T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
742 PM CDT SAT MAY 19 2012

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  POLK COUNTY IN NORTHWEST WISCONSIN...
  ST. CROIX COUNTY IN WEST CENTRAL WISCONSIN...

* UNTIL 845 PM CDT

* AT 739 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING DAMAGING WINDS OF 60 MPH. THIS STORM WAS LOCATED NEAR
  CUSHING...OR ABOUT 10 MILES NORTHWEST OF BALSAM LAKE...AND MOVING
  NORTHEAST AT 35 MPH.  NICKEL SIZE HAIL MAY ALSO ACCOMPANY THESE
  DAMAGING WINDS.

LOCATIONS IN THE WARNING INCLUDE...
  AMERY...
  NEW RICHMOND...
  BALSAM LAKE...
  CENTURIA...
  ST CROIX FALLS...
  DRESSER...
  OSCEOLA...
  WANDEROOS...
  STAR PRAIRIE...
  CLEAR LAKE...
  DEER PARK...
  SOMERSET...
  CYLON...
  FOREST...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4486 9217 4486 9276 4495 9275 4506 9278
      4511 9274 4515 9276 4531 9273 4544 9264
      4547 9270 4564 9266 4565 9254 4573 9252
      4573 9216
TIME...MOT...LOC 0042Z 227DEG 32KT 4553 9262
WIND...HAIL 60MPH 0.88IN

$$
1 follow-up statement
303 
WWUS53 KMPX 200109
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
809 PM CDT SAT MAY 19 2012

WIC095-109-200145-
/O.CON.KMPX.SV.W.0078.000000T0000Z-120520T0145Z/
ST. CROIX WI-POLK WI-
809 PM CDT SAT MAY 19 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR POLK AND ST.
CROIX COUNTIES UNTIL 845 PM CDT...

AT 807 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A LINE OF
SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THESE
STORMS WERE LOCATED ALONG A LINE EXTENDING FROM CLAM FALLS TO BALSAM
LAKE TO SOMERSET...MOVING NORTHEAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  NEW RICHMOND...AMERY...BALDWIN...CLAM FALLS...WANDEROOS...
  WOODVILLE...STAR PRAIRIE...HERSEY...WILSON...CYLON...EMERALD...DEER
  PARK...GLENWOOD CITY...FOREST AND CLEAR LAKE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4486 9217 4486 9276 4495 9275 4506 9278
      4511 9274 4515 9276 4531 9273 4544 9264
      4547 9270 4564 9266 4565 9254 4573 9252
      4573 9216
TIME...MOT...LOC 0109Z 227DEG 32KT 4566 9232 4545 9245
          4512 9262
WIND...HAIL <50MPH 1.00IN

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 7:05 PM CDTSevere Thunderstorm WarningMPXPolk55 min
May 19, 7:31 PM CDTSevere Thunderstorm WarningMPXPolk59 min
May 20, 12:38 PM CDTSpecial Weather StatementMPXEau Claire52 min

Nearby

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