Alert archive / Minnesota / Severe Thunderstorm Warnings in 2004

Severe Thunderstorm Warning 69, NWS Twin Cities, MN

April 18, 20044 counties in Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Apr 18, 2004, 8:17 PM CDT for 4 counties in Minnesota. It was in force for 58 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, 8:17 PM CDT (01:17 UTC)
Expired: Apr 18, 2004, 9:15 PM CDT
In force: 58 min
Issued by: NWS Twin Cities, MN
Area: Counties, with a storm outline in the text

Counties Faribault County, MN, Freeborn County, MN, Steele County, MN, Waseca County, MN

The radar

The Minneapolis radar (KMPX), 108 km from the middle of the area, began a volume at 01:18 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.

Issued	Product	Office	Lasted
Apr 18, 4:40 PM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 1.3 hours before the alert went out and 108 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: 671 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 2341 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 244 m²/s²
0-3 km storm-relative helicity: 328 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.7

Open this sounding in Storm Lab

The text

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

178 
WUUS53 KMPX 190117
SVRMPX
MNC043-047-147-161-190215-

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

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WASECA COUNTY IN SOUTH CENTRAL MINNESOTA
  STEELE COUNTY IN SOUTH CENTRAL MINNESOTA
  FARIBAULT COUNTY IN SOUTH CENTRAL MINNESOTA
  FREEBORN COUNTY IN SOUTH CENTRAL MINNESOTA

* UNTIL 915 PM CDT

* AT 817 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM WITH LARGE
  HAIL AND DAMAGING WINDS 7 MILES NORTH OF MINNESOTA LAKE...OR ABOUT
  17 MILES SOUTH OF MANKATO...MOVING EAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
  ALBERT LEA.
  BLUE EARTH.
  WASECA.

THIS IS A DANGEROUS STORM...STAY INDOORS AWAY FROM WINDOWS. SEVERE
THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE
WARNING.

WIND GUSTS TO 70 MPH ARE POSSIBLE...WITH HAIL UP TO NICKEL SIZE.

LAT...LON 4417 9372 4384 9376 4380 9409 4356 9419
          4359 9310 4406 9313

$$

RAH/SEB

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 18, 7:02 PM CDT	Severe Thunderstorm Warning	MPX	Chisago	43 min
Apr 18, 7:02 PM CDT	Severe Thunderstorm Warning	MPX	Nicollet	58 min
Apr 18, 7:12 PM CDT	Severe Thunderstorm Warning	MPX	Dakota, Scott	63 min
Apr 18, 7:13 PM CDT	Severe Thunderstorm Warning	MPX	Ramsey, Washington	47 min
Apr 18, 7:19 PM CDT	Severe Thunderstorm Warning	MPX	Sibley	41 min
Apr 18, 7:22 PM CDT	Severe Thunderstorm Warning	MPX	Blue Earth, Faribault	53 min
Apr 18, 7:29 PM CDT	Severe Thunderstorm Warning	MPX	Martin	61 min
Apr 18, 7:33 PM CDT	Severe Thunderstorm Warning	MPX	Carver	42 min
Apr 18, 7:45 PM CDT	Severe Thunderstorm Warning	MPX	Le Sueur, Rice	60 min
Apr 18, 7:54 PM CDT	Tornado Warning	MPX	Scott	36 min
Apr 18, 8:04 PM CDT	Tornado Warning	MPX	Dakota	26 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2004 Every severe thunderstorm warning 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.