Alert archive / Minnesota / Tornado Watches in 2004

Tornado Watch 173

May 9, 200430 counties in Minnesota; 6 counties in Wisconsin

The Storm Prediction Center issued this tornado watch at May 9, 2004, 3:55 PM CDT for 30 counties in Minnesota; 6 counties in Wisconsin. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 9, 2004, 3:55 PM CDT (20:55 UTC)
Expired
May 9, 2004, 9:00 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center
All 36 counties

Anoka County, MN, Blue Earth County, MN, Brown County, MN, Carver County, MN, Dakota County, MN, Dodge County, MN, Faribault County, MN, Fillmore County, MN, Freeborn County, MN, Goodhue County, MN, Hennepin County, MN, Le Sueur County, MN, Martin County, MN, McLeod County, MN, Meeker County, MN, Mower County, MN, Nicollet County, MN, Olmsted County, MN, Ramsey County, MN, Rice County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Steele County, MN, Wabasha County, MN, Waseca County, MN, Washington County, MN, Watonwan County, MN, Winona County, MN, Wright County, MN, Barron County, WI, Buffalo County, WI, Dunn County, WI, Pepin County, WI, Pierce County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 60 km from the middle of the area, began a volume at 20:57 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.

Warnings issued inside it

24 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 9, 4:05 PM CDTSevere Thunderstorm WarningMPXMeeker, Stearns55 min
May 9, 4:13 PM CDTTornado WarningMPXMeeker, Stearns47 min
May 9, 4:40 PM CDTSevere Thunderstorm WarningMPXCarver, Hennepin, Wright65 min
May 9, 4:49 PM CDTTornado WarningMPXAnoka, Sherburne, Wright26 min
May 9, 4:58 PM CDTSevere Thunderstorm WarningMPXMcLeod47 min
May 9, 5:11 PM CDTTornado WarningMPXCarver, Hennepin49 min
May 9, 5:18 PM CDTSevere Thunderstorm WarningMPXAnoka42 min
May 9, 5:46 PM CDTSevere Thunderstorm WarningMPXSibley44 min
May 9, 5:47 PM CDTSevere Thunderstorm WarningMPXRamsey, Washington58 min
May 9, 5:48 PM CDTSevere Thunderstorm WarningMPXMcLeod42 min
May 9, 5:56 PM CDTSevere Thunderstorm WarningMPXPolk, Saint Croix64 min
May 9, 6:18 PM CDTSevere Thunderstorm WarningMPXDakota, Scott57 min
May 9, 6:23 PM CDTSevere Thunderstorm WarningMPXPierce67 min
May 9, 6:32 PM CDTSevere Thunderstorm WarningMPXSibley58 min
May 9, 6:34 PM CDTSevere Thunderstorm WarningMPXBarron, Dunn, Pepin41 min
May 9, 7:13 PM CDTSevere Thunderstorm WarningMPXScott47 min
May 9, 7:26 PM CDTSevere Thunderstorm WarningMPXPierce64 min
May 9, 7:35 PM CDTSevere Thunderstorm WarningMPXLe Sueur, Nicollet, Sibley55 min
May 9, 7:40 PM CDTSevere Thunderstorm WarningMPXPepin50 min
May 9, 7:46 PM CDTSevere Thunderstorm WarningARXBuffalo59 min
May 9, 7:57 PM CDTSevere Thunderstorm WarningARXWabasha63 min
May 9, 8:22 PM CDTSevere Thunderstorm WarningMPXBrown53 min
May 9, 8:33 PM CDTSevere Thunderstorm WarningMPXLe Sueur, Rice57 min
May 9, 8:48 PM CDTSevere Thunderstorm WarningARXBuffalo, Trempealeau57 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 8.9 hours before the alert went out and 62 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 2004-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 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 2004-05-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 207 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
8 J/kg
Mixed-layer CIN
-483 J/kg
Mixed-layer LCL
802 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
207 m²/s²
0-3 km storm-relative helicity
170 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 092055
SEL3  
SPC WW 092055
MNZ000-WIZ000-100200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 173
NWS STORM PREDICTION CENTER NORMAN OK
355 PM CDT SUN MAY 9 2004

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       SOUTHERN MINNESOTA
       WESTERN WISCONSIN

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 355 PM UNTIL 900
PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 85 STATUTE MILES EAST AND WEST
OF A LINE FROM 40 MILES NORTH OF MINNEAPOLIS MINNESOTA TO 50 MILES
SOUTHWEST OF ROCHESTER MINNESOTA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...CONTINUE...WW 170...WW 171...WW 172...

DISCUSSION...STRONG SUPERCELL OVER WCENTRAL MN WILL CONTINUE
DEVELOPING E/SE INTO A FAVORABLE SHEAR AND INSTABILITY ENVIRONMENT. 
IN ADDITION TO POSSIBLE TORNADOES...VERY DAMAGING  WINDS ARE ALSO
LIKELY.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550.
MEAN STORM MOTION VECTOR 29035.


...HALES

452,0912 432,0913 432,0945 452,0945

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 9, 2:00 PM CDTMesoscale DiscussionSPCBig Stone, Blue Earth, Brown, Carver, Chippewa, Kandiyohi and 19 more3 hr
May 9, 2:30 PM CDTSevere Thunderstorm WatchSPCBenton, Brown, Chippewa, Cottonwood, Isanti, Kanabec and 22 more6 hr
May 9, 3:29 PM CDTMesoscale DiscussionSPCChisago, Dakota, Goodhue, Hennepin, Le Sueur, Ramsey and 4 more91 min
May 9, 4:46 PM CDTMesoscale DiscussionSPCHouston59 min
May 9, 5:38 PM CDTMesoscale DiscussionSPCAnoka, Blue Earth, Brown, Carver, Chisago, Cottonwood and 25 more2 hr
May 8, 9:55 PM CDTMesoscale DiscussionSPCColumbia, Dane, Dodge, Green, Iowa, Jefferson and 9 more2 hr
May 9, 11:48 AM CDTMesoscale DiscussionSPCColumbia, Dane, Dodge, Fond du Lac, Green, Green Lake and 10 more2 hr
May 9, 12:55 PM CDTSevere Thunderstorm WatchSPCKenosha, Milwaukee, Ozaukee, Racine, Washington6 hr
May 9, 2:46 PM CDTMesoscale DiscussionSPCKenosha, Milwaukee, Ozaukee, Racine89 min
May 9, 6:15 PM CDTSevere Thunderstorm WatchSPCAshland, Barron, Bayfield, Douglas, Forest, Iron and 6 more8 hr

Nearby

Tornado Watches in Minnesota, 2004Tornado Watches in Wisconsin, 2004Every tornado watch 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.