Alert archive / Minnesota / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 231, NWS Twin Cities, MN

August 6, 20115 counties in Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 6, 2011, 12:37 PM CDT for 5 counties in Minnesota. It was in force for 53 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 6, 2011, 12:37 PM CDT (17:37 UTC)
Expired
Aug 6, 2011, 1:30 PM CDT
In force
53 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Benton County, MN, Isanti County, MN, Kanabec County, MN, Mille Lacs County, MN, Morrison County, MN

The radar

The Minneapolis radar (KMPX), 118 km from the middle of the area, began a volume at 17:38 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.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 5.6 hours before the alert went out and 118 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 2011-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 690 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 2011-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
690 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
750 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
51 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

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

078 
WUUS53 KMPX 061737
SVRMPX
MNC009-059-065-095-097-061830-
/O.NEW.KMPX.SV.W.0231.110806T1737Z-110806T1830Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1237 PM CDT SAT AUG 6 2011

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN BENTON COUNTY IN CENTRAL MINNESOTA...
  EXTREME NORTHWESTERN ISANTI COUNTY IN EAST CENTRAL MINNESOTA...
  WESTERN KANABEC COUNTY IN EAST CENTRAL MINNESOTA...
  CENTRAL MILLE LACS COUNTY IN EAST CENTRAL MINNESOTA...
  SOUTHEASTERN MORRISON COUNTY IN CENTRAL MINNESOTA...

* UNTIL 130 PM CDT

* AT 1233 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60 MPH.
  THIS STORM WAS LOCATED 6 MILES NORTHWEST OF FORESTON...OR ABOUT 7
  MILES NORTHWEST OF MILACA...AND MOVING NORTHEAST AT 25 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  MILACA...
  MORA...
  FORESTON...
  LEWIS LAKE...
  OGILVIE...

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.

SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE
WARNING. PREPARE TO MOVE TO A PLACE OF SAFETY IN A STURDY STRUCTURE
SUCH AS A BASEMENT OR SMALL INTERIOR ROOM IF A TORNADO IS SPOTTED.

&&

LAT...LON 4613 9341 4576 9313 4569 9380 4585 9393
TIME...MOT...LOC 1737Z 239DEG 23KT 4582 9375
WIND...HAIL 60MPH 1.00IN

$$
1 follow-up statement
263 
WWUS53 KMPX 061758
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1258 PM CDT SAT AUG 6 2011

MNC009-097-061813-
/O.CAN.KMPX.SV.W.0231.000000T0000Z-110806T1830Z/
BENTON MN-MORRISON MN-
1258 PM CDT SAT AUG 6 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MORRISON AND
NORTHEASTERN BENTON COUNTIES IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA.

LAT...LON 4613 9341 4592 9325 4578 9317 4576 9313
      4573 9348 4574 9351 4573 9351 4571 9371
      4577 9376 4590 9377
TIME...MOT...LOC 1758Z 239DEG 23KT 4589 9358

$$

MNC065-095-061830-
/O.CON.KMPX.SV.W.0231.000000T0000Z-110806T1830Z/
KANABEC MN-MILLE LACS MN-
1258 PM CDT SAT AUG 6 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL MILLE
LACS AND WESTERN KANABEC COUNTIES UNTIL 130 PM CDT...

AT 1252 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND DAMAGING
WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 8 MILES NORTH OF
MILACA...MOVING NORTHEAST AT 25 MPH.

LOCATIONS IMPACTED INCLUDE...
  MORA...LEWIS LAKE...OGILVIE AND BRUNSWICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM HAS EXHIBITED SOME WEAK ROTATION. TORNADOES CAN DEVELOP
QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH ONE IS NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE... SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

&&

LAT...LON 4613 9341 4592 9325 4578 9317 4576 9313
      4573 9348 4574 9351 4573 9351 4571 9371
      4577 9376 4590 9377
TIME...MOT...LOC 1758Z 239DEG 23KT 4589 9358
WIND...HAIL 60MPH 1.00IN

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 10:55 PM CDTAreal Flood AdvisoryMPXKandiyohi, Meeker, Sherburne, Wright3 hr
Aug 6, 10:59 AM CDTAreal Flood AdvisoryMPXDouglas, Mille Lacs, Morrison, Todd4 hr
Aug 6, 11:59 AM CDTSpecial Weather StatementMPXMorrison61 min
Aug 6, 1:20 PM CDTSevere Thunderstorm WarningMPXChisago, Isanti, Kanabec31 min
Aug 6, 2:35 PM CDTSpecial Weather StatementMPXAnoka25 min
Aug 6, 3:18 PM CDTSpecial Weather StatementMPXWashington27 min
Aug 6, 3:29 PM CDTSevere Thunderstorm WarningMPXRamsey, Washington46 min
Aug 6, 5:36 PM CDTSpecial Weather StatementMPXDouglas24 min
Aug 6, 6:59 PM CDTSpecial Weather StatementMPXStearns46 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2011Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.