Alert archive / South Dakota / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 159, NWS Sioux Falls, SD

August 6, 1986Tripp County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 6, 1986, 8:27 PM CDT for Tripp County, South Dakota. It was in force for 63 min. 5 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Aug 6, 1986, 8:27 PM CDT (01:27 UTC)
Expired
Aug 6, 1986, 9:30 PM CDT
In force
63 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Tripp County, SD

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

TimeReportWhereRemark
Aug 6, 8:30 PM CDTHail 4.5Tripp, SD
Aug 6, 8:50 PM CDTHail 1Tripp, SD
Aug 6, 8:50 PM CDTThunderstorm Wind 0Tripp, SD
Aug 6, 9:05 PM CDTThunderstorm Wind 70Tripp, SD
Aug 6, 9:10 PM CDTThunderstorm Wind 0Tripp, SD

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Aberdeen, SD (KHON), launched 00:00Z, 1.5 hours before the alert went out and 209 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 1986-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1002 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 1986-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 33 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
1002 J/kg
Mixed-layer CIN
-71 J/kg
Mixed-layer LCL
1489 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
33 m²/s²
0-3 km storm-relative helicity
92 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.0

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.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Aug 6, 3:52 PM CDT, 4 hours 35 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
345 PM CDT 6 AUG 1986

...A TORNADO WATCH IS IN EFFECT UNTIL 900 PM CDT FOR PARTS OF CENTRAL
AND MUCH OF EASTERN SOUTH DAKOTA...

AT 330 PM CDT...SCATTERED INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN
CONTINUED OVER PARTS OF CENTRAL AND NORTHEAST SOUTH DAKOTA AND INTO
SOUTHEAST NORTH DAKOTA.

THESE STORMS WERE MOSTLY NORTHWEST OF A LINE FROM MISSION TO BRITTON
WITH THE HEAVIEST STORMS LOCATED JUST SOUTH OF BELVIDERE...JUST WEST
OF BARNARD AND 10 MILES NORTHWEST OF MIDLAND.

MOVEMENT WAS SOUTHEAST AT 25 MILES AN HOUR.

EDDY/PFEIFFER
Special weather statement, Aug 6, 4:33 PM CDT, 3 hours 54 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
430 PM CDT WED AUG 6 1986

...TORNADO WATCH IN EFFECT FOR PARTS OF CENTRAL AND EASTERN SOUTH
DAKOTA UNTIL 9 PM CDT...

AT 425 PM CDT SCATTERED INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN
HAVE CONTINUED TO DEVELOP MAINLY IN CENTRAL SOUTH DAKOTA FROM SOUTH
OF MOBRIDGE ON SOUTHWEST TO SOUTHEAST OF RAPID CITY. A STRONG THUNDER/
STORM WITH VERY HEAVY RAIN WAS APPROACHING WHITE RIVER LIN SOUTH/CENTRAL
SOUTH DAKOTA. ALL THESE THUNDERSTORMS WERE MOVING EAST/SOUTHEAST AT
ABOUT 25 MPH AND ARE CAPABLE OF DEVELOPING LARGE HAIL..DAMAGING WINDS..
HEAVY RAINS..AND FREQUENT LIGHTNING.

RYRHOLM
Special weather statement, Aug 6, 4:41 PM CDT, 3 hours 46 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
440 PM CDT 6 AUG 1986

...A TORNADO WATCH IS IN EFFECT UNTIL 900 PM CDT FOR PARTS OF CENTRAL
AND MUCH OF EASTERN SOUTH DAKOTA...

AT 430 PM CDT...SCATTERED INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN
CONTINUED OVER PARTS OF CENTRAL SOUTH DAKOTA.

THESE STORMS WERE MOSTLY NORTHWEST OF A LINE 15 MILES WEST TO 50 MILES
NORTHEAST OF PIERRE. THE STRONGEST STORMS WERE LOC^ATED 15 MILES
NORTHWEST OF PIERRE AND 30 MILES SOUTHEAST OF MOBRIDGE.

MOVEMENT WAS SOUTHEAST AT 30 MILES AN HOUR.

EDDY/MORRIS

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 6, 8:03 PM CDTSevere Thunderstorm WarningFSDBrule, Charles Mix, Gregory57 min
Aug 6, 9:04 PM CDTSevere Thunderstorm WarningFSDTripp56 min
Aug 6, 9:25 PM CDTSevere Thunderstorm WarningFSDGregory65 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 1986Every severe thunderstorm warning in 1986

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.