Alert archive / Minnesota / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 302, NWS Twin Cities, MN

August 11, 2007Blue Earth County, Steele County, Waseca County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 11, 2007, 9:36 PM CDT for Blue Earth County, Steele County, Waseca County, Minnesota. It was in force for 54 min. 6 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 11, 2007, 9:36 PM CDT (02:36 UTC)
Expired
Aug 11, 2007, 10:30 PM CDT
In force
54 min
Issued by
NWS Twin Cities, MN
Area
Counties, with a storm outline in the text

Counties Blue Earth County, MN, Steele County, MN, Waseca County, MN

The radar

The Minneapolis radar (KMPX), 85 km from the middle of the area, began a volume at 02:36 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 11, 10:15 PM CDTTSTM WND DMGWaseca, MNNUMEROUS REPORTS OF 12 TO 18 INCH TREES DOWNED. TIME ESTIMATED.
Aug 11, 10:16 PM CDTHAIL 1Waseca, MN
Aug 11, 10:20 PM CDTHAIL 0.75Waseca, MNTREE KNOCKED DOWN.
Aug 11, 10:23 PM CDTHAIL 0.884 S Waseca, MN
Aug 11, 10:30 PM CDTHAIL 0.754 E Waseca, MNREPORTED ON THE WASECA/STEELE COUNTY LINE.
Aug 11, 10:30 PM CDTHAIL 0.759 W Owatonna, MNREPORTED ON THE STEELE/WASECA COUNTY LINE.

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 11, 6:21 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 2.6 hours before the alert went out and 84 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 00:00Z on 2007-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3342 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2007-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 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
3342 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
1149 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
56 m²/s²
Significant tornado parameter
0.9
Supercell composite
5.6

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KMPX 120236
SVRMPX
MNC013-147-161-120330-
/O.NEW.KMPX.SV.W.0302.070812T0236Z-070812T0330Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
936 PM CDT SAT AUG 11 2007

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BLUE EARTH COUNTY IN SOUTH CENTRAL MINNESOTA...
  WASECA COUNTY IN SOUTH CENTRAL MINNESOTA...
  STEELE COUNTY IN SOUTH CENTRAL MINNESOTA...

* UNTIL 1030 PM CDT

* AT 932 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM...
  CAPABLE OF PRODUCING NICKEL SIZE HAIL...AND DAMAGING WINDS IN      
  EXCESS OF 60 MPH.  THIS STORM WAS LOCATED ALONG A LINE FROM        
  FARIBAULT TO MANKATO...AND MOVING SOUTHEAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MAPLETON...
  JANESVILLE...
  WASECA...
  OWATONNA...
  NEW RICHLAND...
  MEDFORD...
  ELLENDALE...
  BLOOMING PRAIRIE...

STAY INDOORS...AND AWAY FROM WINDOWS.

LAT...LON 4423 9397 4414 9405 4414 9420 4385 9431
      4386 9305 4419 9307 4420 9374

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 7:02 PM CDTSevere Thunderstorm WarningMPXRamsey, Washington58 min
Aug 11, 7:41 PM CDTSevere Thunderstorm WarningMPXCarver, McLeod64 min
Aug 11, 7:55 PM CDTSevere Thunderstorm WarningMPXWashington65 min
Aug 11, 7:57 PM CDTSevere Thunderstorm WarningMPXScott63 min
Aug 11, 8:01 PM CDTSevere Thunderstorm WarningMPXDakota59 min
Aug 11, 8:16 PM CDTSevere Thunderstorm WarningMPXLe Sueur, Rice59 min
Aug 11, 8:26 PM CDTSevere Thunderstorm WarningMPXChisago, Isanti64 min
Aug 11, 8:32 PM CDTSevere Thunderstorm WarningMPXGoodhue58 min
Aug 11, 8:43 PM CDTSevere Thunderstorm WarningMPXNicollet62 min
Aug 11, 8:58 PM CDTSevere Thunderstorm WarningMPXDakota32 min
Aug 11, 9:13 PM CDTSevere Thunderstorm WarningMPXLe Sueur, Rice47 min
Aug 11, 10:27 PM CDTSevere Thunderstorm WarningMPXFreeborn, Steele, Waseca63 min
Aug 11, 11:31 PM CDTSevere Thunderstorm WarningMPXFreeborn27 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2007Every severe thunderstorm warning in 2007

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.