Alert archive / Minnesota / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 1, NWS Twin Cities, MN

April 9, 2011Brown County, Redwood County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Apr 9, 2011, 9:09 AM CDT for Brown County, Redwood County, Minnesota. It was in force for 40 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 9, 2011, 9:09 AM CDT (14:09 UTC)
Expired: Apr 9, 2011, 9:49 AM CDT
In force: 40 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), 134 km from the middle of the area, began a volume at 14:08 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
Apr 9, 9:29 AM CDT	HAIL 0.75	Walnut Grove, 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, 2.2 hours before the alert went out and 152 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 458 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 73 m²/s²
0-3 km storm-relative helicity: 192 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.

463 
WUUS53 KMPX 091409
SVRMPX
MNC015-127-091515-
/O.NEW.KMPX.SV.W.0001.110409T1409Z-110409T1515Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
909 AM CDT SAT APR 9 2011

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 1015 AM CDT

* AT 907 AM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60 MPH.
  THIS STORM WAS LOCATED 5 MILES SOUTH OF TRACY...OR ABOUT 13 MILES
  NORTHEAST OF SLAYTON...AND MOVING EAST AT 35 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  REVERE...
  LAMBERTON...
  SANBORN...
  SPRINGFIELD...
  EVAN...

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.

THIS STORM HAS A HISTORY OF PRODUCING LARGE DAMAGING HAIL. SEEK 
SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS!

&&

LAT...LON 4426 9560 4440 9479 4413 9472 4410 9510
      4419 9512 4419 9559 4420 9561 4423 9561
TIME...MOT...LOC 1409Z 260DEG 29KT 4416 9559
WIND...HAIL 60MPH 1.00IN

$$

RAH

2 follow-up statements

362 
WWUS53 KMPX 091433
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
933 AM CDT SAT APR 9 2011

MNC015-127-091515-
/O.CON.KMPX.SV.W.0001.000000T0000Z-110409T1515Z/
REDWOOD MN-BROWN MN-
933 AM CDT SAT APR 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR WESTERN BROWN
AND SOUTHERN REDWOOD COUNTIES UNTIL 1015 AM CDT...

AT 930 AM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS STORM WAS
LOCATED NEAR REVERE...OR 24 MILES NORTHEAST OF SLAYTON...MOVING EAST
AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  LAMBERTON...SANBORN...SPRINGFIELD...EVAN...WANDA AND COBDEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...LARGE 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 LARGE HAIL. SEEK SHELTER NOW
INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS!

&&

LAT...LON 4421 9548 4424 9549 4428 9548 4440 9479
      4413 9472 4410 9510 4419 9512 4419 9547
TIME...MOT...LOC 1433Z 260DEG 29KT 4421 9534
WIND...HAIL <50MPH 1.00IN

$$

RAH

534 
WWUS53 KMPX 091449
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
949 AM CDT SAT APR 9 2011

MNC015-127-091459-
/O.CAN.KMPX.SV.W.0001.000000T0000Z-110409T1515Z/
REDWOOD MN-BROWN MN-
949 AM CDT SAT APR 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN BROWN AND SOUTHERN
REDWOOD 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.

LAT...LON 4421 9548 4424 9549 4428 9548 4440 9479
      4413 9472 4410 9510 4419 9512 4419 9547
TIME...MOT...LOC 1449Z 260DEG 29KT 4425 9519

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 9, 11:12 AM CDT	Special Weather Statement	MPX	Nicollet, Sibley	48 min
Apr 9, 1:45 PM CDT	Special Weather Statement	MPX	Rice	45 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2011 Every severe thunderstorm warning in 2011

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.