Alert archive / South Dakota / Tornado Warnings in 1986

Tornado Warning 25, NWS Aberdeen, SD

August 6, 1986Walworth County, South Dakota

NWS Aberdeen, SD issued this tornado warning at Aug 6, 1986, 5:15 PM CDT for Walworth County, South Dakota. It was in force for 30 min.

The area

The counties it named.

The facts

Issued
Aug 6, 1986, 5:15 PM CDT (22:15 UTC)
Expired
Aug 6, 1986, 5:45 PM CDT
In force
30 min
Issued by
NWS Aberdeen, SD
Area
Whole counties

County Walworth County, SD

The radar

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

The nearest sounding before it

Aberdeen, SD (KHON), launched 12:00Z, 10.3 hours before the alert went out and 141 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 1986-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 649 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 1986-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -13 square meters per square second.1939Sfc1 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
649 J/kg
Mixed-layer CIN
-88 J/kg
Mixed-layer LCL
970 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
-13 m²/s²
0-3 km storm-relative helicity
27 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KABR 062215 RRA
TORABR
SDC129-062245-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
TORNADO WARNING
NATIONAL WEATHER SERVICE ABERDEEN SD
515 PM CDT WED AUG 6 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING 
EFFECTIVE UNTIL 545 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

NORTH CENTRAL SOUTH DAKOTA...SOUTHEAST WALWORTH

SOME OF THE CITIES INCLUDED IN THIS WARNING ARE LOWRY AND
THE SWAN LAKE AREA.

AT 510 PM CDT  A TORNADO WAS REPORTED BY THE WALWORTH
 COUNTY SHERIFF 4 MILES NORTHEAST OF AKASKA OR 20 MILES
 SOUTHEAST OF MOBRIDGE MOVING SOUTHEAST.

IF YOU ARE IN THE PATH OF THIS TORNADO...YOU SHOULD GO TO A BASEMENT
SHELTER IF AVAILABLE. OTHERWISE GO TO A CENTRAL INTERIOR ROOM ON THE
LOWEST FLOOR POSSIBLE. CARS AND MOBILE HOMES SHOULD BE ABANDONED FOR
A REINFORCED BUILDING.

STUDNICKA

What forecasters said that day

The local office's own words before this tornado 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, 1:36 PM CDT, 3 hours 39 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
130 PM CDT WED AUG 6 1986

...LINE OF INTENSE THUNDERSTORMS MOVING ACROSS NORTH CENTRAL SOUTH
   DAKOTA...

AT 125 PM CDT RADAR INDICATED A LINE OF INTENSE THUNDERSTORMS EXTENDING
FROM SOUTHEAST OF BISMARCK NORTH DAKOTA SOUTHWARD TO AKASKA ON THE
MISSOURI RIVER SOUTH OF MOBRIDGE MOVING EAST SOUTHEAST AT 30 MPH.

THESE THUNDERSTORMS WILL BE MOVING ACROSS THE WEST PORTIONS OF BOTH
MCPHERSON AND EDMUNDS COUNTIES OF NORTH CENTRAL SOUTH DAKOTA BETWEEN
145 PM CDT AND 245 PM CDT THIS EARLY WEDNESDAY AFTERNOON.

PERIODS OF VERY HEAVY RAIN..SMALL HAIL AND WIND TO 50 MPH CAN BE
EXPECTED WITH THE PASAGE OF THESE THUNDERSTORMS. PERSOSNS WITHIN THE
PATH SHOULD TAKE CARE AND BE PREPARED TO GO TO A PKACE OF SAFETY.
 STUDNICKA
Special weather statement, Aug 6, 1:48 PM CDT, 3 hours 27 minutes before
SPECIAL WEATHER STATEMENT...REPEAT FOR WEBSTER STATE RADIO...
NATIONAL WEATHER SERVICE ABERDEEN SD
130 PM CDT WED AUG 6 1986

...LINE OF INTENSE THUNDERSTORMS MOVING ACROSS NORTH CENTRAL SOUTH
   DAKOTA...

AT 125 PM CDT RADAR INDICATED A LINE OF INTENSE THUNDERSTORMS EXTENDING
FROM SOUTHEAST OF BISMARCK NORTH DAKOTA SOUTHWARD TO AKASKA ON THE
MISSOURI RIVER SOUTH OF MOBRIDGE MOVING EAST SOUTHEAST AT 30 MPH.

THESE THUNDERSTORMS WILL BE MOVING ACROSS THE WEST PORTIONS OF BOTH
MCPHERSON AND EDMUNDS COUNTIES OF NORTH CENTRAL SOUTH DAKOTA BETWEEN
145 PM CDT AND 245 PM CDT THIS EARLY WEDNESDAY AFTERNOON.

PERIODS OF VERY HEAVY RAIN..SMALL HAIL AND WIND TO 50 MPH CAN BE
EXPECTED WITH THE PASAGpE OF THESE THUNDERSTORMS. PERSONS WITHIN THE
PATH SHOULD TAKE CARE AND BE PREPARED TO GO TO A PKACE OF SAFETY.
 STUDNICKA
Special weather statement, Aug 6, 3:43 PM CDT, 1 hour 32 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
340 PM CDT WED AUG 6 1986

...TORNADO WATCH FOR PORTIONS OF CENTRAL AND EASTERN SOUTH DAKOTA
   UNTIL 900 PM CDT.

AT 335 PM CDT RADAR INDICATED A VERY INTENSE THUNDERSTORM IN THE
SOUTHEAST PORTION OF DEWEY COUNTY OR 30 MILES WEST OF GETTYSBURG
MOVING EAST SOUTHEAST AT 25 MPH.

THIS THUNDERSTORM WILL MOVE INTO THE MISSOURI RIVER AREA NEAR THE
WHITLOCK CROSSING AREA BETWEEN 415 PM CDT AND 500 PM CDT. BOATERS
SHOULD PREPARE TO LEAVE THE WATER AREAS AS SOON AS POSSIBLE DUE
TO VERY HEAVY RAIN..SMALL HAIL AND WIND GUST TO NEAR 50 MPH.

THIS STORM COULD BECOME SEVERE WITH LITTLE ADVANCED NOTICE, SO
BE VERY WATCHFULL.
 STUDNICKA
Special weather statement, Aug 6, 4:48 PM CDT, 27 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
445 PM CDT WED AUG 6 1986

...TORNADO WATCH FOR PORTIONS OF CENTRAL AND EASTERN SOUTH DAKOTA
   UNTIL 900 PM CDT...

...INTENSE THUNDERSTORMS CONTINUE TO DEVELOPE OVER THE MISSOURI
   RIVER IN NORTH CENTRAL SOUTH DAKOTA.

AT 440 PM CDT RADAR INDICATED INTENSE THUNDERSTORMS EXTENDING FROM
THE NORTH DAKOTA BORDOR NEAR POLLOCK IN CAMPBELL COUNTY SOUTH TO
THE WHITLOCK CROSSING ON U.S. RT 212 WITH THE ONLY BARRON AREA
BEING BETWEEN MOBRIDGE AND AKASKA. ADDITIONAL SHOWERS AND THUNDER/
STORMS IS EXPECTED TO FILL IN THIS VOID WITHIN THE NEXT HOUR.

BOATERS SHOULD LEAVE THE WATER AREAS DUE TO PERIODS OF HEAVY RAIN..
SMALL HAIL ANpD WIND GUSTS TO 50 MPH WITH THE PASSAGE OF THESE
STORMS.

THESE STORMS CONTINUE TO MOVE EAST SOUTHEAST AT 25 MPH AND WILL
PASS OVER CAMPBELL..WALWORTH AND POTTER COUNTIES BY 630 PM CDT.
 STUDNICKA

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 6, 5:06 PM CDTSevere Thunderstorm WarningABRHughes69 min
Aug 6, 6:38 PM CDTSevere Thunderstorm WarningABRBuffalo, Lyman67 min

Nearby

Tornado Warnings in South Dakota, 1986Every tornado warning in 1986Tornadoes 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; the sounding from the Mesonet's radiosonde archive.