Alert archive / South Dakota / Tornado Watches in 1999

Tornado Watch 592

July 27, 199916 counties in South Dakota

The Storm Prediction Center issued this tornado watch at Jul 27, 1999, 4:00 PM CDT for 16 counties in South Dakota. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jul 27, 1999, 4:00 PM CDT (21:00 UTC)
Expired
Jul 27, 1999, 9:00 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Beadle County, SD, Bennett County, SD, Brule County, SD, Buffalo County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jackson County, SD, Jerauld County, SD, Jones County, SD, Lyman County, SD, Mellette County, SD, Oglala Lakota County, SD, Stanley County, SD, Todd County, SD, Tripp County, SD

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 27, 4:07 PM CDTSevere Thunderstorm WarningUNRJackson48 min
Jul 27, 4:15 PM CDTSevere Thunderstorm WarningABRHyde, Sully50 min
Jul 27, 4:55 PM CDTSevere Thunderstorm WarningUNRJackson, Mellette65 min
Jul 27, 5:03 PM CDTSevere Thunderstorm WarningABRHand, Hyde62 min
Jul 27, 6:05 PM CDTSevere Thunderstorm WarningUNRJackson35 min
Jul 27, 6:25 PM CDTTornado WarningFSDBeadle, Kingsbury65 min
Jul 27, 8:29 PM CDTSevere Thunderstorm WarningFSDBeadle51 min

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 9.0 hours before the alert went out and 247 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 1999-07-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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 1999-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 121 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
3 J/kg
Mixed-layer CIN
-442 J/kg
Mixed-layer LCL
1364 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
121 m²/s²
0-3 km storm-relative helicity
155 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.

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 27, 2:30 PM CDTTornado WatchSPCBrown, Clark, Codington, Day, Deuel, Faulk and 5 more6 hr
Jul 27, 6:30 PM CDTTornado WatchSPCAurora, Beadle, Bon Homme, Brookings, Brule, Charles Mix and 21 more6 hr

Nearby

Tornado Watches in South Dakota, 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.