Alert archive / Minnesota / Tornado Warnings in 2004

Tornado Warning 9, NWS Twin Cities, MN

April 18, 2004Brown County, Minnesota

NWS Twin Cities, MN issued this tornado warning at Apr 18, 2004, 6:45 PM CDT for Brown County, Minnesota. It was in force for 45 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
Apr 18, 2004, 6:45 PM CDT (23:45 UTC)
Expired
Apr 18, 2004, 7:30 PM CDT
In force
45 min
Issued by
NWS Twin Cities, MN
Area
Counties, with a storm outline in the text

County Brown County, MN

The radar

The Minneapolis radar (KMPX), 126 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 18, 6:35 PM CDTTornado WatchSPC5 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.8 hours before the alert went out and 124 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 2004-04-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 680 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 12:00Z on 2004-04-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 361 square meters per square second.1939587897Sfc1 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
680 J/kg
Mixed-layer CIN
-274 J/kg
Mixed-layer LCL
697 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
361 m²/s²
0-3 km storm-relative helicity
401 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.3

Open this sounding in Storm Lab

The text

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

784 
WFUS53 KMPX 182345
TORMPX
MNC015-190030-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
646 PM CDT SUN APR 18 2004

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  BROWN COUNTY IN SOUTH CENTRAL MINNESOTA

* UNTIL 730 PM CDT

* AT 646 PM CDT...RADAR INDICATED A DEVELOPING TORNADO 4 MILES WEST
  OF COMFREY...OR ABOUT 19 MILES NORTH OF WINDOM...MOVING NORTHEAST
  AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
  COBDEN.
  COMFREY.
  SLEEPY EYE.
  SPRINGFIELD.

GO TO THE BASEMENT OR A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

LAT...LON 4417 9513 4402 9499 4415 9480 4422 9440
          4439 9469

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 17, 8:13 PM CDTSevere Thunderstorm WarningMPXFaribault, Martin47 min
Apr 17, 8:33 PM CDTSevere Thunderstorm WarningMPXSteele42 min
Apr 17, 8:33 PM CDTSevere Thunderstorm WarningMPXFreeborn57 min
Apr 17, 8:47 PM CDTSevere Thunderstorm WarningMPXBlue Earth58 min
Apr 17, 9:00 PM CDTSevere Thunderstorm WarningMPXFaribault45 min
Apr 17, 9:30 PM CDTSevere Thunderstorm WarningMPXFreeborn60 min
Apr 17, 9:39 PM CDTSevere Thunderstorm WarningMPXWaseca51 min
Apr 17, 9:44 PM CDTSevere Thunderstorm WarningMPXFaribault46 min
Apr 17, 10:19 PM CDTTornado WarningMPXFreeborn26 min
Apr 17, 11:27 PM CDTSevere Thunderstorm WarningMPXSteele48 min
Apr 17, 11:55 PM CDTSevere Thunderstorm WarningMPXRice50 min
Apr 18, 12:07 AM CDTSevere Thunderstorm WarningMPXLe Sueur38 min
Apr 18, 12:15 AM CDTSevere Thunderstorm WarningMPXDakota, Scott45 min
Apr 18, 12:33 AM CDTSevere Thunderstorm WarningMPXLac qui Parle, Yellow Medicine42 min
Apr 18, 12:49 AM CDTSevere Thunderstorm WarningMPXDakota, Goodhue41 min
Apr 18, 1:10 AM CDTSevere Thunderstorm WarningMPXYellow Medicine35 min
Apr 18, 1:26 AM CDTSevere Thunderstorm WarningMPXChippewa49 min
Apr 18, 1:29 AM CDTSevere Thunderstorm WarningMPXDakota, Goodhue, Washington31 min
Apr 18, 1:50 AM CDTSevere Thunderstorm WarningMPXKandiyohi40 min
Apr 18, 4:18 AM CDTSevere Thunderstorm WarningMPXDouglas, Todd42 min
Apr 18, 4:59 AM CDTSevere Thunderstorm WarningMPXTodd31 min
Apr 18, 6:24 AM CDTSevere Thunderstorm WarningMPXMille Lacs, Morrison36 min
Apr 18, 6:43 AM CDTSevere Thunderstorm WarningMPXKanabec47 min
Apr 18, 3:24 PM CDTSevere Thunderstorm WarningMPXSherburne36 min
Apr 18, 3:27 PM CDTSevere Thunderstorm WarningMPXBenton, Mille Lacs, Morrison, Stearns63 min
Apr 18, 3:46 PM CDTSevere Thunderstorm WarningMPXIsanti, Kanabec59 min
Apr 18, 3:52 PM CDTTornado WarningMPXIsanti, Kanabec23 min
Apr 18, 3:54 PM CDTTornado WarningMPXIsanti, Kanabec21 min
Apr 18, 3:57 PM CDTSevere Thunderstorm WarningMPXSherburne33 min
Apr 18, 4:00 PM CDTSevere Thunderstorm WarningMPXMeeker, Wright45 min
Apr 18, 4:08 PM CDTTornado WarningMPXSherburne37 min
Apr 18, 4:15 PM CDTTornado WarningMPXKanabec30 min
Apr 18, 4:27 PM CDTTornado WarningMPXIsanti48 min
Apr 18, 4:42 PM CDTSevere Thunderstorm WarningMPXChisago48 min
Apr 18, 4:56 PM CDTSevere Thunderstorm WarningMPXMeeker, Wright49 min
Apr 18, 5:15 PM CDTSevere Thunderstorm WarningMPXSherburne30 min
Apr 18, 5:17 PM CDTSevere Thunderstorm WarningMPXAnoka, Isanti58 min
Apr 18, 5:18 PM CDTSevere Thunderstorm WarningMPXBrown, Redwood42 min
Apr 18, 5:34 PM CDTSevere Thunderstorm WarningMPXChisago, Isanti41 min
Apr 18, 5:34 PM CDTTornado WarningMPXBrown26 min
Apr 18, 5:46 PM CDTSevere Thunderstorm WarningMPXCarver, McLeod, Renville, Sibley59 min
Apr 18, 5:47 PM CDTSevere Thunderstorm WarningMPXWright43 min
Apr 18, 5:52 PM CDTSevere Thunderstorm WarningMPXSherburne38 min
Apr 18, 5:58 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin47 min
Apr 18, 5:59 PM CDTSevere Thunderstorm WarningMPXBrown, Nicollet, Redwood61 min
Apr 18, 6:02 PM CDTTornado WarningMPXBrown, Redwood43 min
Apr 18, 6:16 PM CDTSevere Thunderstorm WarningMPXChisago44 min
Apr 18, 6:22 PM CDTSevere Thunderstorm WarningMPXRamsey, Washington53 min
Apr 18, 6:34 PM CDTSevere Thunderstorm WarningMPXWright26 min
Apr 18, 6:42 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin48 min
Apr 18, 6:50 PM CDTSevere Thunderstorm WarningMPXCarver, McLeod40 min
Apr 18, 6:52 PM CDTSevere Thunderstorm WarningMPXMartin, Watonwan38 min

Nearby

Tornado Warnings in Minnesota, 2004Every tornado warning in 2004Tornadoes in 2004

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.