Alert archive / Minnesota / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 16, NWS Twin Cities, MN

May 1, 2012Brown County, Redwood County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at May 1, 2012, 6:43 PM CDT for Brown County, Redwood County, Minnesota. It was in force for 62 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
May 1, 2012, 6:43 PM CDT (23:43 UTC)
Expired
May 1, 2012, 7:45 PM CDT
In force
62 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Brown County, MN, Redwood County, MN

The radar

The Sioux Falls radar (KFSD), 140 km from the middle of the area, began a volume at 23:44 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.

What was reported inside it

TimeReportWhereRemark
May 1, 7:10 PM CDTHAIL 12 N Walnut Grove, 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
May 1, 2:59 PM CDTTornado WatchSPC6 hr
May 1, 6:10 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.7 hours before the alert went out and 146 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 2012-05-01Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2012-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 163 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
1291 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
196 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.

630 
WUUS53 KMPX 012343
SVRMPX
MNC015-127-020045-
/O.NEW.KMPX.SV.W.0016.120501T2343Z-120502T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
643 PM CDT TUE MAY 1 2012

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHWESTERN BROWN COUNTY IN SOUTH CENTRAL MINNESOTA...
  SOUTHERN REDWOOD COUNTY IN SOUTHWEST MINNESOTA...

* UNTIL 745 PM CDT

* AT 641 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS OF 60 MPH. THIS
  STORM WAS LOCATED NEAR TRACY...OR ABOUT 18 MILES NORTHEAST OF
  SLAYTON...AND MOVING EAST AT 25 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  REVERE...
  LAMBERTON...
  WABASSO...
  SANBORN...
  SPRINGFIELD...
  CLEMENTS...
  MORGAN...
  COMFREY...
  WALNUT GROVE...  

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.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT TUESDAY EVENING
FOR SOUTHERN MINNESOTA.

&&

LAT...LON 4435 9559 4448 9487 4411 9487 4411 9509
      4420 9511 4420 9560
TIME...MOT...LOC 2342Z 260DEG 20KT 4422 9556
WIND...HAIL 60MPH 1.00IN

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 1, 4:41 AM CDTSpecial Weather StatementMPXDouglas, Morrison, Pope, Stevens, Todd79 min
May 1, 4:12 PM CDTSevere Thunderstorm WarningMPXPope, Stearns33 min
May 1, 4:40 PM CDTSevere Thunderstorm WarningMPXSherburne, Stearns, Wright35 min
May 1, 4:43 PM CDTSevere Thunderstorm WarningMPXPope, Stearns47 min
May 1, 4:46 PM CDTTornado WarningMPXPope, Stearns44 min
May 1, 5:07 PM CDTTornado WarningMPXSherburne, Stearns, Wright38 min
May 1, 5:08 PM CDTSevere Thunderstorm WarningMPXChippewa, Lac qui Parle, Yellow Medicine67 min
May 1, 5:09 PM CDTTornado WarningMPXStearns36 min
May 1, 5:17 PM CDTSevere Thunderstorm WarningMPXRedwood, Yellow Medicine32 min
May 1, 5:23 PM CDTSevere Thunderstorm WarningMPXBenton, Morrison, Stearns37 min
May 1, 5:38 PM CDTTornado WarningMPXSherburne37 min
May 1, 5:44 PM CDTTornado WarningMPXBenton, Sherburne, Stearns46 min
May 1, 6:08 PM CDTSevere Thunderstorm WarningMPXRedwood52 min
May 1, 6:14 PM CDTSevere Thunderstorm WarningMPXIsanti, Sherburne46 min
May 1, 6:25 PM CDTTornado WarningMPXBenton, Sherburne35 min
May 1, 6:56 PM CDTSevere Thunderstorm WarningMPXBenton, Mille Lacs, Sherburne34 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.