Alert archive / Minnesota / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 41, NWS Twin Cities, MN

May 21, 2011Todd County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at May 21, 2011, 9:11 PM CDT for Todd County, Minnesota. It was in force for 64 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: May 21, 2011, 9:11 PM CDT (02:11 UTC)
Expired: May 21, 2011, 10:15 PM CDT
In force: 64 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

County Todd County, MN

The radar

The Minneapolis radar (KMPX), 165 km from the middle of the area, began a volume at 02:12 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 21, 9:20 PM CDT	HAIL 1	8 W Long Prairie, MN
May 21, 9:25 PM CDT	HAIL 1	5 W Long Prairie, 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 00:00Z, 2.2 hours before the alert went out and 163 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: 1091 J/kg
Mixed-layer CIN: -11 J/kg
Mixed-layer LCL: 922 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 348 m²/s²
0-3 km storm-relative helicity: 424 m²/s²
Significant tornado parameter: 2.3
Supercell composite: 12.8

Open this sounding in Storm Lab

The text

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

350 
WUUS53 KMPX 220211
SVRMPX
MNC153-220315-
/O.NEW.KMPX.SV.W.0041.110522T0211Z-110522T0315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
911 PM CDT SAT MAY 21 2011

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN TODD COUNTY IN CENTRAL MINNESOTA...

* UNTIL 1015 PM CDT

* AT 907 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING QUARTER SIZE HAIL. THIS STORM WAS LOCATED NEAR OSAKIS...
  OR ABOUT 12 MILES SOUTHWEST OF LONG PRAIRIE...AND MOVING NORTHEAST
  AT 20 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  LONG PRAIRIE...
  CLOTHO...
  CLARISSA...
  BROWERVILLE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM
WINDOWS.

REPORT ANY SIGNIFICANT WIND OR HAIL DAMAGE TO THE NEAREST LAW
ENFORCEMENT AGENCY...FOR RELAY TO THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4609 9467 4578 9503 4578 9513 4595 9515
      4622 9493
TIME...MOT...LOC 0211Z 219DEG 18KT 4592 9507
WIND...HAIL <50MPH 1.00IN

$$

2 follow-up statements

215 
WWUS53 KMPX 220229
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
929 PM CDT SAT MAY 21 2011

MNC153-220315-
/O.CON.KMPX.SV.W.0041.000000T0000Z-110522T0315Z/
TODD MN-
929 PM CDT SAT MAY 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR TODD COUNTY
UNTIL 1015 PM CDT...

AT 926 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS STORM WAS
LOCATED NEAR CLOTHO...OR 6 MILES WEST OF LONG PRAIRIE...MOVING
NORTHEAST AT 25 MPH.

IN ADDITION...AT 920 PM QUARTER SIZE HAIL WAS REPORTED 8 MILES WEST 
OF LONG PRAIRIE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  LONG PRAIRIE...CLARISSA AND BROWERVILLE.

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 4609 9467 4578 9503 4578 9513 4595 9515
      4622 9493
TIME...MOT...LOC 0229Z 222DEG 21KT 4599 9497
WIND...HAIL <50MPH 1.00IN

$$

845 
WWUS53 KMPX 220243
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
943 PM CDT SAT MAY 21 2011

MNC153-220315-
/O.CON.KMPX.SV.W.0041.000000T0000Z-110522T0315Z/
TODD MN-
943 PM CDT SAT MAY 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL TODD
COUNTY UNTIL 1015 PM CDT...

AT 939 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS STORM WAS 
LOCATED NEAR BROWERVILLE...MOVING NORTHEAST AT 25 MPH.

LOCATIONS IMPACTED INCLUDE...
  BROWERVILLE AND CLARISSA.

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 4592 9506 4595 9514 4622 9493 4609 9467
      4590 9489
TIME...MOT...LOC 0244Z 215DEG 22KT 4606 9489
WIND...HAIL <50MPH 1.00IN

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 7:00 PM CDT	Tornado Warning	MPX	Anoka, Hennepin	45 min
May 21, 7:24 PM CDT	Severe Thunderstorm Warning	MPX	Hennepin, Wright	51 min
May 21, 7:25 PM CDT	Tornado Warning	MPX	Anoka	35 min
May 21, 7:46 PM CDT	Special Weather Statement	MPX	Pope	44 min
May 21, 8:00 PM CDT	Areal Flood Advisory	MPX	Anoka, Hennepin, Wright	3 hr
May 21, 8:06 PM CDT	Severe Thunderstorm Warning	MPX	Martin	39 min
May 21, 8:44 PM CDT	Severe Thunderstorm Warning	MPX	Martin	61 min
May 21, 8:59 PM CDT	Special Weather Statement	MPX	Todd	61 min
May 21, 9:25 PM CDT	Severe Thunderstorm Warning	MPX	Watonwan	50 min
May 21, 9:42 PM CDT	Severe Thunderstorm Warning	MPX	Redwood	48 min
May 21, 10:12 PM CDT	Special Weather Statement	MPX	Yellow Medicine	48 min
May 21, 10:26 PM CDT	Special Weather Statement	MPX	Redwood	34 min
May 21, 10:43 PM CDT	Severe Thunderstorm Warning	MPX	Brown, Martin, Redwood, Watonwan	62 min
May 21, 10:43 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Pope, Renville, Stevens, Swift	47 min
May 22, 12:46 AM CDT	Special Weather Statement	MPX	Le Sueur, Rice, Steele, Waseca	44 min
May 22, 10:57 AM CDT	Special Weather Statement	MPX	Dakota, Goodhue, Rice	48 min
May 22, 11:02 AM CDT	Special Weather Statement	MPX	Anoka, Hennepin, Ramsey	43 min
May 22, 12:38 PM CDT	Severe Thunderstorm Warning	MPX	Le Sueur, Rice, Steele, Waseca	52 min
May 22, 12:53 PM CDT	Severe Thunderstorm Warning	MPX	Carver, Le Sueur, Scott	52 min
May 22, 1:23 PM CDT	Severe Thunderstorm Warning	MPX	Dakota, Goodhue, Rice, Steele	67 min
May 22, 1:35 PM CDT	Special Weather Statement	MPX	Hennepin	40 min
May 22, 2:05 PM CDT	Severe Thunderstorm Warning	MPX	Goodhue	40 min
May 22, 2:10 PM CDT	Tornado Warning	MPX	Anoka, Hennepin, Ramsey	35 min
May 22, 2:24 PM CDT	Tornado Warning	MPX	Anoka, Hennepin, Ramsey	36 min
May 22, 2:45 PM CDT	Tornado Warning	MPX	Anoka, Ramsey, Washington	30 min
May 22, 3:10 PM CDT	Tornado Warning	MPX	Chisago, Washington	35 min
May 22, 3:34 PM CDT	Tornado Warning	MPX	Chisago	41 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.