Alert archive / South Dakota / Tornado Watches in 1999

Tornado Watch 418

June 7, 1999Boyd County, Keya Paha County, Nebraska; 31 counties in South Dakota

The Storm Prediction Center issued this tornado watch at Jun 7, 1999, 6:15 PM CDT for Boyd County, Keya Paha County, Nebraska; 31 counties in South Dakota. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jun 7, 1999, 6:15 PM CDT (23:15 UTC)
Expired
Jun 8, 1999, 12:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
All 33 counties

Boyd County, NE, Keya Paha County, NE, Aurora County, SD, Bennett County, SD, Brule County, SD, Buffalo County, SD, Butte County, SD, Charles Mix County, SD, Custer County, SD, Douglas County, SD, Fall River County, SD, Faulk County, SD, Gregory County, SD, Haakon County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jackson County, SD, Jerauld County, SD, Jones County, SD, Lawrence County, SD, Lyman County, SD, Meade County, SD, Mellette County, SD, Oglala Lakota County, SD, Pennington County, SD, Potter County, SD, Spink County, SD, Stanley County, SD, Sully County, SD, Todd County, SD, Tripp County, SD, Ziebach County, SD

The radar

The Rapid City radar (KUDX), 90 km from the middle of the area, began a volume at 23:15 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

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

IssuedProductOfficeCountiesLasted
Jun 7, 6:47 PM CDTSevere Thunderstorm WarningABRLyman48 min
Jun 7, 6:57 PM CDTSevere Thunderstorm WarningFSDGregory33 min
Jun 7, 7:07 PM CDTSevere Thunderstorm WarningUNRTripp43 min
Jun 7, 7:13 PM CDTSevere Thunderstorm WarningUNRCuster47 min
Jun 7, 7:33 PM CDTSevere Thunderstorm WarningABRLyman32 min
Jun 7, 7:40 PM CDTSevere Thunderstorm WarningFSDBrule50 min
Jun 7, 7:42 PM CDTSevere Thunderstorm WarningABRHughes33 min
Jun 7, 7:44 PM CDTSevere Thunderstorm WarningUNRTripp46 min
Jun 7, 7:50 PM CDTSevere Thunderstorm WarningFSDCharles Mix25 min
Jun 7, 7:54 PM CDTSevere Thunderstorm WarningUNRCuster61 min
Jun 7, 8:09 PM CDTTornado WarningFSDBrule, Charles Mix36 min
Jun 7, 8:22 PM CDTSevere Thunderstorm WarningABRLyman63 min
Jun 7, 8:31 PM CDTSevere Thunderstorm WarningUNRTripp19 min
Jun 7, 8:39 PM CDTTornado WarningFSDAurora36 min
Jun 7, 8:45 PM CDTSevere Thunderstorm WarningFSDBrule45 min
Jun 7, 9:01 PM CDTSevere Thunderstorm WarningLBFKeya Paha59 min
Jun 7, 9:12 PM CDTTornado WarningFSDAurora48 min
Jun 7, 9:16 PM CDTSevere Thunderstorm WarningFSDBrule, Charles Mix, Gregory44 min
Jun 7, 9:34 PM CDTSevere Thunderstorm WarningLBFBoyd66 min
Jun 7, 10:00 PM CDTSevere Thunderstorm WarningLBFKeya Paha45 min
Jun 7, 10:09 PM CDTSevere Thunderstorm WarningUNRLawrence31 min
Jun 7, 10:18 PM CDTSevere Thunderstorm WarningFSDGregory42 min
Jun 7, 10:28 PM CDTSevere Thunderstorm WarningUNRMeade47 min
Jun 7, 11:14 PM CDTSevere Thunderstorm WarningUNRMeade61 min
Jun 7, 11:28 PM CDTSevere Thunderstorm WarningUNRZiebach47 min

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 11.3 hours before the alert went out and 273 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 1999-06-07Temperature 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 1999-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -180 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1219 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
-180 m²/s²
0-3 km storm-relative helicity
-56 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

Nearby

Tornado Watches in South Dakota, 1999Tornado Watches in Nebraska, 1999Every tornado watch in 1999

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.