Alert archive / Minnesota / Tornado Warnings in 2012

Tornado Warning 4, NWS Sioux Falls, SD

April 15, 2012Lyon County, Minnesota

NWS Sioux Falls, SD issued this tornado warning at Apr 15, 2012, 3:41 PM CDT for Lyon County, Minnesota. It was in force for 19 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 15, 2012, 3:41 PM CDT (20:41 UTC)
Expired
Apr 15, 2012, 4:00 PM CDT
In force
19 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon

County Lyon County, MN

The radar

The Sioux Falls radar (KFSD), 111 km from the middle of the area, began a volume at 20:41 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 15, 4:10 PM CDTHAIL 12 N Ghent, MN

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
Apr 15, 3:37 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 8.7 hours before the alert went out and 189 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 2012-04-15Temperature 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 2012-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 125 square meters per square second.1939587897117136Sfc1 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
502 m above ground
0-6 km bulk shear
79 kt
0-1 km storm-relative helicity
125 m²/s²
0-3 km storm-relative helicity
222 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.

885 
WFUS53 KFSD 152041
TORFSD
MNC083-152100-
/O.NEW.KFSD.TO.W.0004.120415T2041Z-120415T2100Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
341 PM CDT SUN APR 15 2012

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  LYON COUNTY IN SOUTHWEST MINNESOTA...

* UNTIL 400 PM CDT

* AT 342 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
  TRACKING A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS
  DANGEROUS STORM WAS LOCATED NEAR RUSSELL...OR 12 MILES SOUTHWEST OF
  MARSHALL...AND MOVING NORTHEAST AT 30 MPH.

* THIS TORNADIC STORM WILL BE NEAR...
  MARSHALL AND GHENT AROUND 400 PM CDT...

OTHER LOCATIONS IMPACTED BY THIS TORNADIC THUNDERSTORM INCLUDE LYND.

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 4446 9565 4422 9596 4427 9608 4430 9608
      4457 9594
TIME...MOT...LOC 2042Z 216DEG 28KT 4434 9596

$$

LAFLIN
2 follow-up statements
590 
WWUS53 KFSD 152053
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
353 PM CDT SUN APR 15 2012

MNC083-152100-
/O.CON.KFSD.TO.W.0004.000000T0000Z-120415T2100Z/
LYON MN-
353 PM CDT SUN APR 15 2012

...A TORNADO WARNING REMAINS IN EFFECT FOR CENTRAL LYON COUNTY UNTIL
400 PM CDT...

AT 353 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED NEAR CAMDEN STATE PARK...OR 8 MILES WEST OF
MARSHALL...MOVING NORTHEAST AT 30 MPH.

THIS DANGEROUS STORM WILL BE NEAR...
  GHENT AROUND 400 PM CDT...

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 4431 9592 4435 9601 4457 9594 4446 9565
TIME...MOT...LOC 2053Z 208DEG 26KT 4444 9593

$$

LAFLIN
482 
WWUS53 KFSD 152059
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
359 PM CDT SUN APR 15 2012

MNC083-152109-
/O.EXP.KFSD.TO.W.0004.000000T0000Z-120415T2100Z/
LYON MN-
359 PM CDT SUN APR 15 2012

...THE TORNADO WARNING FOR CENTRAL LYON COUNTY WILL EXPIRE AT 400 PM
CDT...

THE TORNADO THREAT HAS DIMINISHED...THEREFORE THE TORNADO WARNING HAS
EXPIRED. HOWEVER...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT
FOR THE AREA.

LAT...LON 4431 9592 4435 9601 4457 9594 4446 9565
TIME...MOT...LOC 2059Z 208DEG 26KT 4448 9590

$$

LAFLIN

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 15, 2:48 PM CDTSevere Thunderstorm WarningFSDPipestone27 min
Apr 15, 3:05 PM CDTSevere Thunderstorm WarningFSDLincoln, Lyon, Murray, Pipestone25 min
Apr 15, 3:38 PM CDTSevere Thunderstorm WarningFSDLincoln, Lyon37 min
Apr 15, 4:14 PM CDTTornado WarningFSDLyon16 min
Apr 15, 5:10 PM CDTHigh Wind WarningFSDLincoln, Pipestone, Rock11 hr

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.