Alert archive / South Dakota / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 659

August 31, 200221 counties in South Dakota

The Storm Prediction Center issued this severe thunderstorm watch at Aug 31, 2002, 6:20 PM CDT for 21 counties in South Dakota. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Aug 31, 2002, 6:20 PM CDT (23:20 UTC)
Expired
Sep 1, 2002, 12:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
All 21 counties

Brown 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, Hyde County, SD, Marshall County, SD, McPherson County, SD, Potter County, SD, Roberts County, SD, Spink County, SD, Sully County, SD, Walworth County, SD

The radar

The Aberdeen radar (KABR), 89 km from the middle of the area, began a volume at 23:19 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

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

IssuedProductOfficeCountiesLasted
Aug 31, 6:31 PM CDTSevere Thunderstorm WarningABRHyde, Sully44 min
Aug 31, 7:49 PM CDTSevere Thunderstorm WarningABRFaulk41 min
Aug 31, 8:29 PM CDTSevere Thunderstorm WarningABRFaulk, Potter46 min
Aug 31, 9:13 PM CDTSevere Thunderstorm WarningABRFaulk, Potter32 min
Aug 31, 9:41 PM CDTSevere Thunderstorm WarningABREdmunds34 min
Aug 31, 9:45 PM CDTSevere Thunderstorm WarningABRFaulk30 min
Aug 31, 10:40 PM CDTSevere Thunderstorm WarningABRMcPherson20 min
Aug 31, 11:49 PM CDTSevere Thunderstorm WarningABRBrown, McPherson26 min

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 11.3 hours before the alert went out and 105 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 2002-08-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1772 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 12:00Z on 2002-08-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 350 square meters per square second.193958Sfc1 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
1772 J/kg
Mixed-layer CIN
-278 J/kg
Mixed-layer LCL
849 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
350 m²/s²
0-3 km storm-relative helicity
340 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.1

Open this sounding in Storm Lab

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.