Alert archive / South Dakota / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 488

July 2, 200212 counties in South Dakota

The Storm Prediction Center issued this severe thunderstorm watch at Jul 2, 2002, 10:30 AM CDT for 12 counties in South Dakota. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jul 2, 2002, 10:30 AM CDT (15:30 UTC)
Expired
Jul 2, 2002, 3:00 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Beadle County, SD, Brookings County, SD, Clark County, SD, Codington County, SD, Deuel County, SD, Faulk County, SD, Grant County, SD, Hamlin County, SD, Hand County, SD, Hyde County, SD, Kingsbury County, SD, Spink County, SD

The radar

The Aberdeen radar (KABR), 63 km from the middle of the area, began a volume at 15:30 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.

IssuedProductOfficeCountiesLasted
Jul 2, 10:42 AM CDTSevere Thunderstorm WarningABRFaulk18 min
Jul 2, 10:43 AM CDTSevere Thunderstorm WarningABRSpink47 min
Jul 2, 11:32 AM CDTSevere Thunderstorm WarningABRSpink28 min
Jul 2, 11:57 AM CDTSevere Thunderstorm WarningABRClark48 min

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 3.5 hours before the alert went out and 3 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 12:00Z on 2002-07-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2002-07-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -24 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1723 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
-24 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 021522
SEL8  
SPC WW 021513
SDZ000-022000-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 488
STORM PREDICTION CENTER NORMAN OK
1013 AM CDT TUE JUL 2 2002

THE STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

   EASTERN SOUTH DAKOTA                       

EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 1030 AM UNTIL 300
PM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 40 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 75 MILES WEST NORTHWEST OF HURON
SOUTH DAKOTA TO 35 MILES EAST SOUTHEAST OF WATERTOWN SOUTH DAKOTA.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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.  SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.

DISCUSSION...THUNDERSTORMS EXPECTED TO PERSIST IN WARM ADVECTION
ZONE NE OF SRN SD SURFACE WAVE.  WAVE AND ASSOCIATED INFLOW SHOULD
BE MAINTAINED BY CONTINUED EWD MOVEMENT UPPER IMPULSE NOW OVER SE
SASKATCHEWAN.  AREA WIND AND THERMODYNAMIC DATA SUGGEST THAT
EXISTING STORM CLUSTER MAY EXHIBIT BOTH UPWIND AND DOWNWIND
PROPAGATION.  ROTATING UPDRAFTS WILL SUPPORT CONTINUED HAIL THREAT
DESPITE WARM MEAN TEMPERATURES...WITH AN INCREASED THREAT FOR HIGH
WIND IF ACTIVITY DOES INDEED DEVELOP IN THE DOWNWIND /ESE/
DIRECTION. 

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM
MOTION VECTOR 28030.

...CORFIDI

452,0993 451,0962 440,0962 441,0993

Nearby

Severe Thunderstorm Watches in South Dakota, 2002Every severe thunderstorm watch in 2002

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.