Alert archive / Minnesota / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 23, NWS Twin Cities, MN

May 1, 2012Brown County, Redwood County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at May 1, 2012, 8:13 PM CDT for Brown County, Redwood County, Minnesota. It was in force for 25 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, 8:13 PM CDT (01:13 UTC)
Expired: May 1, 2012, 8:38 PM CDT
In force: 25 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 Minneapolis radar (KMPX), 142 km from the middle of the area, began a volume at 01:13 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

Time	Report	Where	Remark
May 1, 8:30 PM CDT	HAIL 0.88	W Lamberton, MN	40 MPH ALSO WITH THIS STORM...TIME ESTIMATED FROM RADAR

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.

Issued	Product	Office	Lasted
May 1, 2:59 PM CDT	Tornado Watch	SPC	6 hr
May 1, 6:10 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 1.2 hours before the alert went out and 140 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 279 J/kg
Mixed-layer CIN: -111 J/kg
Mixed-layer LCL: 1279 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 227 m²/s²
0-3 km storm-relative helicity: 393 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 4.9

Open this sounding in Storm Lab

The text

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

561 
WUUS53 KMPX 020113
SVRMPX
MNC015-127-020215-
/O.NEW.KMPX.SV.W.0023.120502T0113Z-120502T0215Z/

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

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

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

* UNTIL 915 PM CDT

* AT 808 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS OF 60 MPH. THIS
  STORM WAS LOCATED NEAR REVERE...OR ABOUT 22 MILES NORTHEAST OF
  SLAYTON...AND MOVING NORTHEAST AT 35 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  REVERE...
  LAMBERTON...
  SANBORN...
  SPRINGFIELD...
  CLEMENTS...
  MORGAN...

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 4411 9509 4420 9512 4420 9557 4433 9551
      4445 9486 4429 9487 4410 9496
TIME...MOT...LOC 0113Z 237DEG 30KT 4422 9538
WIND...HAIL 60MPH 1.00IN

$$

1 follow-up statement

957 
WWUS53 KMPX 020138
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
838 PM CDT TUE MAY 1 2012

MNC015-127-020153-
/O.CAN.KMPX.SV.W.0023.000000T0000Z-120502T0215Z/
BROWN MN-REDWOOD MN-
838 PM CDT TUE MAY 1 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN REDWOOD AND WESTERN
BROWN COUNTIES IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR
PROPERTY...HOWEVER SMALL HAIL AND GUSTY WINDS ARE STILL POSSIBLE WITH
THIS THUNDERSTORM.

LAT...LON 4411 9509 4420 9512 4420 9557 4433 9551
      4445 9486 4429 9487 4410 9496
TIME...MOT...LOC 0138Z 237DEG 30KT 4433 9513

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
May 1, 7:08 PM CDT	Severe Thunderstorm Warning	MPX	Sherburne, Stearns, Wright	52 min
May 1, 7:23 PM CDT	Special Weather Statement	MPX	Isanti, Kanabec	52 min
May 1, 7:24 PM CDT	Severe Thunderstorm Warning	MPX	Carver, McLeod, Sibley	51 min
May 1, 7:30 PM CDT	Severe Thunderstorm Warning	MPX	Chisago, Isanti, Kanabec	45 min
May 1, 7:55 PM CDT	Special Weather Statement	MPX	Anoka	50 min
May 1, 8:08 PM CDT	Severe Thunderstorm Warning	MPX	Anoka, Chisago, Isanti	37 min
May 1, 8:09 PM CDT	Severe Thunderstorm Warning	MPX	Brown, Nicollet, Sibley	66 min
May 1, 9:24 PM CDT	Special Weather Statement	MPX	Nicollet, Sibley	51 min
May 1, 10:11 PM CDT	Special Weather Statement	MPX	Blue Earth, Faribault, Le Sueur, Martin, Nicollet	49 min
May 1, 11:12 PM CDT	Special Weather Statement	MPX	Freeborn, Rice, Steele, Waseca	48 min
May 2, 5:22 PM CDT	Severe Thunderstorm Warning	MPX	Blue Earth, Brown, Watonwan	53 min
May 2, 5:50 PM CDT	Tornado Warning	MPX	Blue Earth, Brown, Nicollet, Watonwan	40 min
May 2, 6:20 PM CDT	Severe Thunderstorm Warning	MPX	Blue Earth, Le Sueur, Nicollet, Waseca	55 min
May 2, 6:45 PM CDT	Severe Thunderstorm Warning	MPX	Goodhue, Rice, Steele	60 min
May 2, 6:45 PM CDT	Severe Thunderstorm Warning	MPX	Brown, Redwood	60 min
May 2, 6:58 PM CDT	Severe Thunderstorm Warning	MPX	Le Sueur, Rice, Steele, Waseca	47 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2012 Every 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.