Alert archive / Minnesota / Tornado Warnings in 2012

Tornado Warning 10, NWS Twin Cities, MN

April 21, 2012Martin County, Watonwan County, Minnesota

NWS Twin Cities, MN issued this tornado warning at Apr 21, 2012, 5:01 PM CDT for Martin County, Watonwan County, Minnesota. It was in force for 44 min. 1 report 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
Apr 21, 2012, 5:01 PM CDT (22:01 UTC)
Expired
Apr 21, 2012, 5:45 PM CDT
In force
44 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon

Counties Martin County, MN, Watonwan County, MN

The radar

The Minneapolis radar (KMPX), 150 km from the middle of the area, began a volume at 22:04 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
Apr 21, 5:17 PM CDTFUNNEL CLOUD7 Wnw Trimont, MN

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

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 10.0 hours before the alert went out and 149 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 12:00Z on 2012-04-21Temperature 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 12:00Z on 2012-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 33 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1566 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
33 m²/s²
0-3 km storm-relative helicity
85 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

568 
WFUS53 KMPX 212201
TORMPX
MNC091-165-212245-
/O.NEW.KMPX.TO.W.0010.120421T2201Z-120421T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
501 PM CDT SAT APR 21 2012

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN MARTIN COUNTY IN SOUTH CENTRAL MINNESOTA...
  SOUTHWESTERN WATONWAN COUNTY IN SOUTH CENTRAL MINNESOTA...

* UNTIL 545 PM CDT

* AT 500 PM CDT...RADAR INDICATED A STORM CAPABLE OF PRODUCING A
  TORNADO. THE MOST DANGEROUS PART OF THE STORM WAS 8 MILES WEST OF
  ODIN...OR ABOUT 4 MILES SOUTH OF MOUNTAIN LAKE...AND MOVING
  SOUTHEAST AT 20 MPH.

* LOCATIONS IN THE WARNING INCLUDE...
  ODIN...
  ORMSBY...
  TRIMONT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

WHEN A TORNADO WARNING IS ISSUED BASED ON RADAR...IT MEANS THAT
STRONG ROTATION HAS BEEN DETECTED IN THE STORM. A TORNADO MAY ALREADY
BE ON THE GROUND...OR IS EXPECTED TO DEVELOP SHORTLY.

&&

LAT...LON 4366 9480 4371 9487 4397 9487 4397 9486
      4397 9485 4385 9459
TIME...MOT...LOC 2201Z 309DEG 19KT 4388 9490

$$
3 follow-up statements
163 
WWUS53 KMPX 212220
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
520 PM CDT SAT APR 21 2012

MNC165-212235-
/O.CAN.KMPX.TO.W.0010.000000T0000Z-120421T2245Z/
WATONWAN MN-
520 PM CDT SAT APR 21 2012

...THE TORNADO WARNING FOR SOUTHWESTERN WATONWAN COUNTY IS
CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA.

LAT...LON 4366 9480 4371 9487 4385 9485 4385 9461
      4384 9460
TIME...MOT...LOC 2220Z 320DEG 19KT 4379 9484

$$

MNC091-212245-
/O.CON.KMPX.TO.W.0010.000000T0000Z-120421T2245Z/
MARTIN MN-
520 PM CDT SAT APR 21 2012

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHWESTERN MARTIN COUNTY
UNTIL 545 PM CDT...

AT 518 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS STORM
WAS LOCATED 7 MILES WEST OF TRIMONT...OR 14 MILES NORTHEAST OF
JACKSON...MOVING SOUTHEAST AT 20 MPH.

LOCATIONS IMPACTED INCLUDE...
  TRIMONT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4366 9480 4371 9487 4385 9485 4385 9461
      4384 9460
TIME...MOT...LOC 2220Z 320DEG 19KT 4379 9484

$$
597 
WWUS53 KMPX 212233
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
533 PM CDT SAT APR 21 2012

MNC091-212245-
/O.CON.KMPX.TO.W.0010.000000T0000Z-120421T2245Z/
MARTIN MN-
533 PM CDT SAT APR 21 2012

...A TORNADO WARNING REMAINS IN EFFECT FOR WEST CENTRAL MARTIN COUNTY
UNTIL 545 PM CDT...

AT 529 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS STORM 
WAS LOCATED ABOUT 5 MILES WEST OF TRIMONT...OR 13 MILES NORTHEAST OF 
JACKSON...MOVING SOUTHEAST AT 20 MPH.

AT 517 PM...A FUNNEL CLOUD WAS REPORTED 8 MILES WEST...NORTHWEST OF 
TRIMONT.  

LOCATIONS IMPACTED INCLUDE...
  TRIMONT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4380 9484 4380 9466 4366 9480 4371 9487
TIME...MOT...LOC 2231Z 320DEG 19KT 4375 9479

$$
905 
WWUS53 KMPX 212244
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
544 PM CDT SAT APR 21 2012

MNC091-212258-
/O.EXP.KMPX.TO.W.0010.000000T0000Z-120421T2245Z/
MARTIN MN-
544 PM CDT SAT APR 21 2012

...THE TORNADO WARNING FOR WEST CENTRAL MARTIN COUNTY WILL EXPIRE AT
545 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS JUST MOVED OUT OF THE WARNED
AREA...HOWEVER DIME SIZE HAIL AND WINDS TO 40 MPH ARE STILL POSSIBLE 
WITH THE THUNDERSTORM.

LAT...LON 4380 9484 4380 9466 4366 9480 4371 9487
TIME...MOT...LOC 2243Z 320DEG 19KT 4370 9473

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 21, 1:50 PM CDTSpecial Weather StatementMPXStevens55 min
Apr 21, 2:04 PM CDTSevere Thunderstorm WarningMPXStevens14 min
Apr 21, 2:28 PM CDTSpecial Weather StatementMPXChippewa, Douglas, Pope, Redwood, Swift62 min
Apr 21, 3:22 PM CDTSevere Thunderstorm WarningMPXBrown, Redwood38 min
Apr 21, 3:29 PM CDTTornado WarningMPXChippewa, Swift46 min
Apr 21, 3:33 PM CDTTornado WarningMPXRedwood28 min
Apr 21, 4:09 PM CDTTornado WarningMPXChippewa, Kandiyohi, Renville36 min
Apr 21, 4:21 PM CDTSpecial Weather StatementMPXPope39 min
Apr 21, 4:49 PM CDTSpecial Weather StatementMPXRenville41 min
Apr 21, 5:53 PM CDTSpecial Weather StatementMPXMartin37 min

Nearby

Tornado Warnings in Minnesota, 2012Every tornado warning in 2012Tornadoes 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.