Alert archive / South Dakota / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 33, NWS Sioux Falls, SD

May 11, 1986Todd County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 11, 1986, 9:32 PM CDT for Todd County, South Dakota. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
May 11, 1986, 9:32 PM CDT (02:32 UTC)
Expired
May 12, 1986, 12:30 AM CDT
In force
3 hr
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Todd 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

Rapid City, SD (KRAP), launched 00:00Z, 2.5 hours before the alert went out and 199 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, Rapid City, SD at 00:00Z on 1986-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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, Rapid City, SD at 00:00Z on 1986-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 87 square meters per square second.1939587897Sfc1 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
5 J/kg
Mixed-layer CIN
-209 J/kg
Mixed-layer LCL
2496 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
87 m²/s²
0-3 km storm-relative helicity
180 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KFSD 120432
SVRFSD
SDC121-120530-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1132 PM CDT SUN MAY 11 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 1230 AM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTY OF

SOUTH CENTRAL SOUTH DAKOTA...TODD

SOME OF THE CITIES INCLUDED IN SOUTHCENTRAL SOUTH DAKOTA ROSEBUD
ST FRANCIS AND MISSION.

AT 1126 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM OVER
WESTCENTRAL TODD COUNTY MOVING TO THE EAST NORTHEAST AT 30
MPH.

IF YOU ARE IN THE PATH OF THIS STORM..YOU SHOULD GET TO A REINFORCED
SHELTER. A SEVERE THUNDERSTORM PRODUCES DAMAGING WINDS IN EXCESS OF
60 MPHp..HAIL 3/4 INCH OR LARGER..DEADLY LIGHTNING..AND HEAVY RAIN
THAT CAN QUICKLY FLOOD A LOW LYING AREA.

KOSCIELSKI

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, May 11, 7:18 PM CDT, 2 hours 14 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
705 PM CDT SUN MAY 11 1986

...THUNDERSTORMS DEVELOP OVER THE CENTRAL...

THUNDERSTORMS WITH VERY HEAVY RAIN HAD DEVELOPED SINCE 615 PM CDT OVER
THE SOUTH CENTRAL AND CENTRAL PARTS OF SOUTH DAKOTA. BRIEF HEAVY RAIN
AND SOME SMALL HAIL MAY BE PRODUCED FROM THE SCATTERED THUNDERSTORMS
OVER THOSE PARTS OF THE STATE. THE THUNDERSTORMS WERE MOVING TO THE
NORTHEAST AT 25 MPH.

AT 700 PM CDT THE THUNDERSTORMS WITH VERY HEAVY RAIN WERE OVER LAKE
FRANCIS CASE..NORTHEAST OF WINNER AND SOUTHWEST OF GANN VALLEY. THE
MOVEMENT OF THESE STORMS WILL TAKE THEM INTO CENTRAL BRULE AND SOUTHERN
HAND COUNTIES RESPECTIVELY. CAMPERS AND BOATEORS IN THE PATHS OF THE
THUNDERSTORMS SHOULD GET OUT OF THE WATER AND BE PREPARED FOR THE
APPROACHING THUNDERSTORMS.
WEILAND
Special weather statement, May 11, 7:20 PM CDT, 2 hours 12 minutes before
SPECIAL WEATHER STATEMENT      CORRECTED
NATIONAL WEATHER SERVICE SIOUX FALLS SD
705 PM CDT SUN MAY 11 1986

...THUNDERSTORMS DEVELOP OVER THE CENTRAL...

THUNDERSTORMS WITH VERY HEAVY RAIN HAD DEVELOPED SINCE 615 PM CDT OVER
THE SOUTH CENTRAL AND CENTRAL PARTS OF SOUTH DAKOTA. BRIEF HEAVY RAIN
AND SOME SMALL HAIL MAY BE PRODUCED FROM THE SCATTERED THUNDERSTORMS
OVER THOSE PARTS OF THE STATE. THE THUNDERSTORMS WERE MOVING TO THE
NORTHEAST AT 25 MPH.

AT 700 PM CDT THE THUNDERSTORMS WITH VERY HEAVY RAIN WERE OVER LAKE
FRANCIS CASE..NORTHEAST OF WINNER AND SOUTHWEST OF GANN VALLEY. THE
MOVEMENT OF THESE STORMS WILL TAKE THEM INTO CENTRAL BRULE AND SOUTHERN
HAND COUNTIES AT 740 PM CDRT RESPECTIVELY. CAMPERS AND BOATERS IN THE
PATHS OF THE THUNDERSTORMS SHOULD GET OUT OF THE WATER AND BE PREPARED
FOR THE APPROACHING THUNDERSTORMS.
WEILAND

The office that day

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

IssuedProductOfficeCountiesLasted
May 11, 7:24 PM CDTSevere Thunderstorm WarningFSDBrule66 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; the sounding from the Mesonet's radiosonde archive.