Alert archive / South Dakota / Tornado Watches in 2004

Tornado Watch 682

August 1, 200432 counties in South Dakota

The Storm Prediction Center issued this tornado watch at Aug 1, 2004, 7:45 PM CDT for 32 counties in South Dakota. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Aug 1, 2004, 7:45 PM CDT (00:45 UTC)
Expired
Aug 2, 2004, 2:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
All 32 counties

Beadle County, SD, Brookings County, SD, Brown County, SD, Buffalo County, SD, Campbell County, SD, Clark County, SD, Codington County, SD, Corson County, SD, Day County, SD, Deuel County, SD, Dewey County, SD, Edmunds County, SD, Faulk County, SD, Grant County, SD, Hamlin County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Marshall County, SD, McPherson County, SD, Miner County, SD, Moody County, SD, Potter County, SD, Roberts County, SD, Sanborn County, SD, Spink County, SD, Stanley County, SD, Sully County, SD, Walworth County, SD

The radar

The Aberdeen radar (KABR), 82 km from the middle of the area, began a volume at 00:46 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

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

IssuedProductOfficeCountiesLasted
Aug 1, 8:43 PM CDTSevere Thunderstorm WarningABRDewey47 min
Aug 1, 9:15 PM CDTSevere Thunderstorm WarningABRPotter, Sully45 min
Aug 1, 9:57 PM CDTSevere Thunderstorm WarningABRHughes, Sully48 min
Aug 1, 10:41 PM CDTSevere Thunderstorm WarningABRHughes, Hyde34 min
Aug 1, 11:12 PM CDTSevere Thunderstorm WarningABRBuffalo, Hand, Hyde33 min
Aug 1, 11:19 PM CDTSevere Thunderstorm WarningFSDBeadle41 min
Aug 1, 11:35 PM CDTSevere Thunderstorm WarningFSDJerauld40 min
Aug 1, 11:42 PM CDTSevere Thunderstorm WarningABRBuffalo, Hand18 min
Aug 1, 11:51 PM CDTSevere Thunderstorm WarningABRClark, Spink54 min
Aug 1, 11:57 PM CDTSevere Thunderstorm WarningFSDSanborn48 min
Aug 1, 11:59 PM CDTSevere Thunderstorm WarningFSDBeadle31 min
Aug 2, 12:11 AM CDTSevere Thunderstorm WarningFSDKingsbury49 min
Aug 2, 12:16 AM CDTSevere Thunderstorm WarningFSDJerauld29 min
Aug 2, 12:23 AM CDTSevere Thunderstorm WarningFSDMiner37 min
Aug 2, 12:56 AM CDTSevere Thunderstorm WarningFSDLake34 min
Aug 2, 1:00 AM CDTSevere Thunderstorm WarningFSDAurora, Douglas, Miner30 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 00:00Z, 0.8 hours before the alert went out and 79 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, Aberdeen, SD at 00:00Z on 2004-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3501 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, Aberdeen, SD at 00:00Z on 2004-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 112 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
3501 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
1092 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
112 m²/s²
0-3 km storm-relative helicity
305 m²/s²
Significant tornado parameter
3.8
Supercell composite
15.7

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 020045
SEL2  
SPC WW 020045
SDZ000-020700-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 682
NWS STORM PREDICTION CENTER NORMAN OK
745 PM CDT SUN AUG 1 2004

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

       CENTRAL AND EASTERN SOUTH DAKOTA

EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 745 PM UNTIL
200 AM 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 65 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 55 MILES SOUTHWEST OF MOBRIDGE SOUTH DAKOTA
TO 30 MILES EAST OF WATERTOWN SOUTH DAKOTA.

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...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 678...SEVERE THUNDERSTORM WATCH NUMBER 681. WATCH
NUMBER 678 681 WILL NOT BE IN EFFECT AFTER 745 PM CDT.
CONTINUE...WW 679...WW 680...

DISCUSSION...RAPIDLY INTENSIFYING SEVERE THUNDERSTORMS OVER NCENTRAL
SD EXPECTED TO MOVE  E/SE INTO A VERY UNSTABLE AIR MASS.  WITH
STRONG VEERING SHEAR PROFILES NOTED ON 00Z ABR SOUNDING...CONDITIONS
NOW FAVORABLE FOR TORNADIC SUPERCELLS. ADDITIONALLY WITH MLCAPES TO
4000 J/KG ERN SD...VERY LARGE HAIL AND DAMAGING DOWNBURST WINDS ARE
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 600.
MEAN STORM MOTION VECTOR 30030.


...HALES

455,1011 455,0963 435,0963 440,1011

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 1, 7:22 PM CDTMesoscale DiscussionSPCBeadle, Brookings, Brown, Campbell, Clark, Codington and 17 more53 min
Aug 1, 10:00 PM CDTMesoscale DiscussionSPCBeadle, Buffalo, Campbell, Edmunds, Faulk, Hand and 7 more60 min
Aug 1, 10:35 PM CDTSevere Thunderstorm WatchSPCAurora, Bon Homme, Brule, Charles Mix, Clay, Davison and 6 more5 hr
Aug 1, 11:29 PM CDTMesoscale DiscussionSPCAurora, Beadle, Bon Homme, Brule, Buffalo, Charles Mix and 19 more61 min
Aug 2, 12:20 AM CDTSevere Thunderstorm WatchSPCLake, Lincoln, Minnehaha, Moody, Union4 hr
Aug 2, 3:02 AM CDTMesoscale DiscussionSPCBon Homme, Clay, Lincoln, Turner, Union, Yankton58 min
Aug 2, 3:12 PM CDTMesoscale DiscussionSPCBeadle, Brookings, Clark, Deuel, Hamlin, Jerauld and 7 more2 hr
Aug 2, 3:50 PM CDTSevere Thunderstorm WatchSPCBrookings, Davison, Hanson, Kingsbury, Lake, McCook and 4 more5 hr
Aug 2, 4:23 PM CDTMesoscale DiscussionSPCBon Homme, Charles Mix, Clay, Douglas, Gregory, Hutchinson and 5 more37 min
Aug 2, 6:30 PM CDTSevere Thunderstorm WatchSPCAurora, Bennett, Bon Homme, Brule, Buffalo, Charles Mix and 17 more6 hr

Nearby

Tornado Watches in South Dakota, 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.