Alert archive / Minnesota / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 239, NWS Twin Cities, MN

August 1, 20125 counties in Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 1, 2012, 6:47 PM CDT for 5 counties in Minnesota. It was in force for 58 min. 2 reports 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
Aug 1, 2012, 6:47 PM CDT (23:47 UTC)
Expired
Aug 1, 2012, 7:45 PM CDT
In force
58 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
0.88 in
Wind
70.0 mph

Counties Brown County, MN, Nicollet County, MN, Redwood County, MN, Renville County, MN, Sibley County, MN

The radar

The Minneapolis radar (KMPX), 130 km from the middle of the area, began a volume at 23:48 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
Aug 1, 7:25 PM CDTHAIL 0.53 Ssw Clements, MN
Aug 1, 7:25 PM CDTHAIL 0.752 Nnw Springfield, 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
Aug 1, 5:12 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.8 hours before the alert went out and 128 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 2012-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 670 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 12:00Z on 2012-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 246 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
670 J/kg
Mixed-layer CIN
-340 J/kg
Mixed-layer LCL
1367 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
246 m²/s²
0-3 km storm-relative helicity
292 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

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

541 
WUUS53 KMPX 012347
SVRMPX
MNC015-103-127-129-143-020045-
/O.NEW.KMPX.SV.W.0239.120801T2347Z-120802T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
647 PM CDT WED AUG 1 2012

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BROWN COUNTY IN SOUTH CENTRAL MINNESOTA...
  NORTHWESTERN NICOLLET COUNTY IN SOUTH CENTRAL MINNESOTA...
  EASTERN REDWOOD COUNTY IN SOUTHWEST MINNESOTA...
  SOUTH CENTRAL RENVILLE COUNTY IN CENTRAL MINNESOTA...
  SOUTHWESTERN SIBLEY COUNTY IN CENTRAL MINNESOTA...

* UNTIL 745 PM CDT

* AT 643 PM CDT...TRAINED SPOTTERS REPORTED A LINE OF SEVERE
  THUNDERSTORMS WITH DESTRUCTIVE WINDS IN EXCESS OF 70 MPH. THESE
  STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 7 MILES EAST OF
  BECHYN TO CLEMENTS TO 5 MILES SOUTH OF TRACY...AND MOVING SOUTHEAST
  AT 35 MPH.  NICKEL SIZE HAIL MAY ALSO ACCOMPANY THESE DAMAGING
  WINDS.

LOCATIONS IN THE WARNING INCLUDE...
  NEW ULM...
  CLEMENTS...
  MORTON...
  REVERE...
  LAMBERTON...
  FRANKLIN...
  MORGAN...
  SANBORN...
  SPRINGFIELD...
  EVAN...
  FAIRFAX...
  SLEEPY EYE...
  GIBBON...
  ST GEORGE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS SITUATION. IF YOU ARE IN THE PATH OF THIS
STORM...PREPARE IMMEDIATELY FOR DESTRUCTIVE WINDS...WHICH CAN UPROOT
TREES...DOWN POWER LINES...AND CAUSE DAMAGE TO ROOFS AND WINDOWS.
EVACUATE MOBILE HOMES AS THEY MAY BE OVERTURNED. HAIL IS ALSO
EXPECTED...WHICH CAN CAUSE MINOR DAMAGE TO VEHICLES AND WINDOWS. SEEK
SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

WIND DAMAGE WITH THIS STORM WILL OCCUR WELL AHEAD OF ANY RAIN OR
LIGHTNING. DO NOT WAIT FOR THE SOUND OF THUNDER BEFORE TAKING COVER.
SEEK SHELTER IMMEDIATELY INSIDE A STURDY STRUCTURE AND STAY AWAY FROM
WINDOWS.

&&

LAT...LON 4411 9511 4419 9512 4419 9557 4438 9521
      4469 9496 4459 9440 4411 9441 4410 9506
TIME...MOT...LOC 2347Z 298DEG 30KT 4464 9488 4433 9508
          4415 9556
WIND...HAIL 70MPH 0.88IN

$$

JLT
4 follow-up statements
710 
WWUS53 KMPX 012356
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
656 PM CDT WED AUG 1 2012

MNC015-103-127-129-143-020045-
/O.CON.KMPX.SV.W.0239.000000T0000Z-120802T0045Z/
BROWN MN-NICOLLET MN-REDWOOD MN-RENVILLE MN-SIBLEY MN-
656 PM CDT WED AUG 1 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHWESTERN
SIBLEY...SOUTH CENTRAL RENVILLE...EASTERN REDWOOD...NORTHWESTERN
NICOLLET AND BROWN COUNTIES UNTIL 745 PM CDT...

AT 653 PM CDT...A LINE OF SEVERE THUNDERSTORMS WERE LOCATED FROM 7 
MILES NORTHEAST OF FRANKLIN TO 5 MILES NORTHWEST OF SPRINGFIELD TO 5 
MILES NORTHEAST OF DOVRAY...MOVING SOUTHEAST AT 35 MPH. 

AT 647 PM...THE REDWOOD FALLS AIRPORT REPORTED A 71 MPH WIND GUST 
WITH THESE STORMS. IN ADDITION...NICKEL SIZE HAIL MAY ALSO ACCOMPANY 
THESE DAMAGING WINDS.

LOCATIONS IMPACTED INCLUDE...
  NEW ULM...MORGAN...SANBORN...SPRINGFIELD...FAIRFAX...EVAN...SLEEPY
  EYE...GIBBON...ST GEORGE...COMFREY...KLOSSNER...HANSKA AND COBDEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS SITUATION. IF YOU ARE IN THE PATH OF THIS
STORM...PREPARE IMMEDIATELY FOR DESTRUCTIVE WINDS...WHICH CAN UPROOT
TREES...DOWN POWER LINES...AND CAUSE DAMAGE TO ROOFS AND WINDOWS.
EVACUATE MOBILE HOMES AS THEY MAY BE OVERTURNED. HAIL IS ALSO
EXPECTED...WHICH CAN CAUSE DAMAGE TO VEHICLES AND WINDOWS. SEEK
SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

THIS STORM HAS A HISTORY OF PRODUCING WIDESPREAD WIND DAMAGE ACROSS 
REDWOOD COUNTY. THIS IS AN EXTREMELY DANGEROUS SITUATION. SEEK 
SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS!

&&

LAT...LON 4411 9511 4419 9512 4419 9557 4438 9521
      4469 9496 4459 9440 4411 9441 4410 9506
TIME...MOT...LOC 2354Z 298DEG 30KT 4461 9481 4430 9501
          4412 9549
WIND...HAIL 70MPH 0.88IN

$$

JLT
770 
WWUS53 KMPX 020011
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
711 PM CDT WED AUG 1 2012

MNC015-103-127-129-143-020045-
/O.CON.KMPX.SV.W.0239.000000T0000Z-120802T0045Z/
BROWN MN-NICOLLET MN-REDWOOD MN-RENVILLE MN-SIBLEY MN-
711 PM CDT WED AUG 1 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHWESTERN
SIBLEY...SOUTH CENTRAL RENVILLE...EASTERN REDWOOD...NORTHWESTERN
NICOLLET AND BROWN COUNTIES UNTIL 745 PM CDT...

AT 706 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A LINE OF SEVERE
THUNDERSTORMS PRODUCING DESTRUCTIVE WINDS IN EXCESS OF 70 MPH.  THESE
STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 7 MILES SOUTH OF
HECTOR TO SPRINGFIELD TO 6 MILES SOUTH OF LAMBERTON TO CURRIE...
MOVING SOUTHEAST AT 35 MPH. NICKEL SIZE HAIL MAY ALSO ACCOMPANY THESE
DAMAGING WINDS.

IN ADDITION...AT 651 PM...A 79 MPH WIND GUST OCCURRED AT THE REDWOOD 
FALLS AIRPORT. 

LOCATIONS IMPACTED INCLUDE...
  NEW ULM...EVAN...FAIRFAX...SLEEPY EYE...GIBBON...COMFREY...ST
  GEORGE...KLOSSNER...HANSKA AND COBDEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS SITUATION. IF YOU ARE IN THE PATH OF THIS
STORM...PREPARE IMMEDIATELY FOR DESTRUCTIVE WINDS...WHICH CAN UPROOT
TREES...DOWN POWER LINES...AND CAUSE DAMAGE TO ROOFS AND WINDOWS.
EVACUATE MOBILE HOMES AS THEY MAY BE OVERTURNED. HAIL IS ALSO
EXPECTED...WHICH CAN CAUSE DAMAGE TO VEHICLES AND WINDOWS. SEEK
SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

THIS STORM HAS A HISTORY OF PRODUCING WIDESPREAD WIND DAMAGE ACROSS 
REDWOOD AND PARTS OF SOUTHERN RENVILLE COUNTIES. THIS IS AN 
EXTREMELY DANGEROUS SITUATION. SEEK SHELTER NOW INSIDE A STURDY 
STRUCTURE AND STAY AWAY FROM WINDOWS!

&&

LAT...LON 4411 9511 4419 9512 4419 9557 4438 9521
      4469 9496 4459 9440 4411 9441 4410 9506
TIME...MOT...LOC 0009Z 298DEG 30KT 4463 9470 4427 9491
          4414 9520 4405 9561
WIND...HAIL 70MPH 0.88IN

$$

JLT
160 
WWUS53 KMPX 020036
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
736 PM CDT WED AUG 1 2012

MNC015-103-127-129-143-020045-
/O.CON.KMPX.SV.W.0239.000000T0000Z-120802T0045Z/
BROWN MN-NICOLLET MN-REDWOOD MN-RENVILLE MN-SIBLEY MN-
736 PM CDT WED AUG 1 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHWESTERN
SIBLEY...SOUTH CENTRAL RENVILLE...SOUTHEASTERN REDWOOD...NORTHWESTERN
NICOLLET AND BROWN COUNTIES UNTIL 745 PM CDT...

AT 734 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A LINE OF SEVERE
THUNDERSTORMS PRODUCING DAMAGING WINDS OF 65 MPH.  THESE STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM GIBBON TO 8 MILES SOUTH OF SLEEPY
EYE TO 6 MILES SOUTHWEST OF COMFREY TO 5 MILES SOUTH OF WESTBROOK...
MOVING SOUTHEAST AT 40 MPH. PENNY SIZE HAIL MAY ALSO ACCOMPANY THESE
DAMAGING WINDS.

LOCATIONS IMPACTED INCLUDE...
  NEW ULM...ST GEORGE...KLOSSNER AND HANSKA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

THIS STORM HAS A HISTORY OF PRODUCING WIDESPREAD WIND DAMAGE ACROSS 
PARTS OF REDWOOD AND RENVILLE COUNTIES. SEEK SHELTER NOW INSIDE A 
STURDY STRUCTURE AND STAY AWAY FROM WINDOWS!

&&

LAT...LON 4411 9511 4419 9512 4420 9525 4436 9507
      4466 9485 4459 9440 4411 9441 4410 9506
TIME...MOT...LOC 0035Z 298DEG 34KT 4455 9449 4418 9471
          4406 9499 4396 9541
WIND...HAIL 60MPH 0.75IN

$$

JLT
937 
WWUS53 KMPX 020042
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
742 PM CDT WED AUG 1 2012

MNC015-103-127-129-143-020057-
/O.EXP.KMPX.SV.W.0239.000000T0000Z-120802T0045Z/
BROWN MN-NICOLLET MN-REDWOOD MN-RENVILLE MN-SIBLEY MN-
742 PM CDT WED AUG 1 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN SIBLEY...SOUTH
CENTRAL RENVILLE...SOUTHEASTERN REDWOOD...NORTHWESTERN NICOLLET AND
BROWN COUNTIES WILL EXPIRE AT 745 PM CDT...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAVE WEAKENED BELOW
SEVERE LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR 
PROPERTY...HOWEVER GUSTY WINDS AND SMALL HAIL ARE STILL POSSIBLE 
WITH THESE THUNDERSTORMS.

LAT...LON 4411 9511 4419 9512 4420 9525 4436 9507
      4466 9485 4459 9440 4411 9441 4410 9506
TIME...MOT...LOC 0042Z 298DEG 34KT 4451 9441 4415 9463
          4403 9491 4393 9533

$$

JLT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 10:10 AM CDTSpecial Weather StatementMPXSherburne50 min
Aug 1, 4:44 PM CDTSpecial Weather StatementMPXYellow Medicine61 min
Aug 1, 4:59 PM CDTSevere Thunderstorm WarningMPXYellow Medicine46 min
Aug 1, 6:02 PM CDTSevere Thunderstorm WarningMPXRedwood, Renville, Yellow Medicine58 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.