Alert archive / South Dakota / Tornado Watches in 2004

Tornado Watch 478

June 15, 20044 states

The Storm Prediction Center issued this tornado watch at Jun 15, 2004, 3:35 PM CDT for 4 states. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: Jun 15, 2004, 3:35 PM CDT (20:35 UTC)
Expired: Jun 15, 2004, 10:00 PM CDT
In force: 6 hr
Issued by: the Storm Prediction Center

All 48 counties

Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Ida County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sac County, IA, Sioux County, IA, Woodbury County, IA, Cottonwood County, MN, Jackson County, MN, Lincoln County, MN, Lyon County, MN, Murray County, MN, Nobles County, MN, Pipestone County, MN, Redwood County, MN, Renville County, MN, Rock County, MN, Yellow Medicine County, MN, Cedar County, NE, Dakota County, NE, Dixon County, NE, Knox County, NE, Pierce County, NE, Wayne County, NE, Bon Homme County, SD, Brookings County, SD, Clay County, SD, Davison County, SD, Deuel County, SD, Hamlin County, SD, Hanson County, SD, Hutchinson County, SD, Kingsbury County, SD, Lake County, SD, Lincoln County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 40 km from the middle of the area, began a volume at 20:39 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

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

Issued	Product	Office	Counties	Lasted
Jun 15, 4:22 PM CDT	Tornado Warning	FSD	Kingsbury	23 min
Jun 15, 4:44 PM CDT	Tornado Warning	FSD	Kingsbury	46 min
Jun 15, 7:52 PM CDT	Severe Thunderstorm Warning	FSD	Brookings, Kingsbury	38 min
Jun 15, 8:25 PM CDT	Tornado Warning	FSD	Brookings	50 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

Aberdeen, SD (KABR), launched 12:00Z, 8.6 hours before the alert went out and 219 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: 37 J/kg
Mixed-layer CIN: -218 J/kg
Mixed-layer LCL: 1709 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 68 m²/s²
0-3 km storm-relative helicity: 98 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 152037
SEL8  
SPC WW 152035
IAZ000-MNZ000-NEZ000-SDZ000-160300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 478
NWS STORM PREDICTION CENTER NORMAN OK
335 PM CDT TUE JUN 15 2004

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

       NORTHWEST IOWA
       SOUTHWEST MINNESOTA
       NORTHEAST NEBRASKA
       SOUTHEAST SOUTH DAKOTA

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 335 PM UNTIL
1000 PM CDT.

TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS ALONG AND 80 STATUTE MILES EAST AND WEST
OF A LINE FROM 40 MILES NORTH NORTHEAST OF BROOKINGS SOUTH DAKOTA
TO 20 MILES SOUTHWEST OF SIOUX CITY IOWA.

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 477...

DISCUSSION...SURFACE LOW VICINITY HON WITH COLD FRONT SWWD AND WARM
FRONT EWD. WARM SECTOR VERY UNSTABLE WITH 30KT SLY LLJ WILL ENHANCE
DEEP LAYER SHEAR FOR TORNADIC SUPERCELLS. SEVERE THUNDERSTORMS
EXPECTED TO DEVELOP RAPIDLY VICINITY SURFACE LOW AND MOVE/PROPAGATE
E/SEWD.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 25030.


...HALES

444,0945 421,0950 421,0981 444,0980

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 15, 1:17 PM CDT	Mesoscale Discussion	SPC	Brown, Chippewa, Cottonwood, Lac qui Parle, Lincoln, Lyon and 6 more	118 min
Jun 14, 9:52 PM CDT	Mesoscale Discussion	SPC	Richardson	113 min
Jun 14, 10:32 PM CDT	Mesoscale Discussion	SPC	Dundy, Franklin, Furnas, Harlan, Hitchcock, Nuckolls and 2 more	88 min
Jun 14, 11:00 PM CDT	Severe Thunderstorm Watch	SPC	Franklin, Furnas, Harlan, Hitchcock, Nuckolls, Red Willow and 2 more	5 hr
Jun 14, 11:25 PM CDT	Severe Thunderstorm Watch	SPC	Gage, Jefferson, Pawnee, Richardson, Saline	5 hr
Jun 15, 1:53 PM CDT	Mesoscale Discussion	SPC	Chase, Deuel, Dundy, Perkins	2 hr
Jun 15, 5:19 PM CDT	Mesoscale Discussion	SPC	Arthur, Blaine, Boyd, Brown, Custer, Garfield and 12 more	116 min
Jun 15, 6:30 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Arthur, Blaine, Brown, Buffalo, Chase and 30 more	6 hr

Nearby

Tornado Watches in South Dakota, 2004 Tornado Watches in Iowa, 2004 Tornado Watches in Minnesota, 2004 Every 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.