Alert archive / South Dakota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 4, NWS Sioux Falls, SD

May 17, 1987McCook County, Minnehaha County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 17, 1987, 4:15 PM CDT for McCook County, Minnehaha County, South Dakota. It was in force for 60 min.

The area

The counties it named.

The facts

Issued
May 17, 1987, 4:15 PM CDT (21:15 UTC)
Expired
May 17, 1987, 5:15 PM CDT
In force
60 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

Counties McCook County, SD, Minnehaha 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, 9.3 hours before the alert went out and 172 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 1987-05-17Temperature 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 1987-05-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1265 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
-19 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 172115
SVRFSD
SDC087-099-172215-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
415 PM CDT SUN MAY 17 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL  515 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN SOUTHEAST SOUTH DAKOTA
          ...MCCOOK...NORTHWESTERN MINNEHAHA
 
SOME CITIES INCLUDED IN THIS WARNING ARE BRIDGEWATER...SALEM AND
HUMBOLDT SOUTH DAKOTA.
 
AT 415 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM 5 MILES SOUTH OF
BRIDEGEWATER 40 MILES SOUTHWEST OF SIOUX FALLS MOVING NORTHEAST
AT 20 MPH.
 
IF YOU ARE IN THE PATH OF THIS STORM...YOU SHOULD GET TO A
REINFORCED SHELTER. A SEVERE THUNDERSTORM PRODUCES WINDS IN EXCESS
OF 60 MPH...HAIL 3/4 INCH OR LARGER...DEADLY LIGHTNING...AND HEAVY
RAIN THAT CAN QUICKLY FLOOD A LOW LYING AREA.
 
JANSEN

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 17, 3:25 PM CDT, 50 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
324 PM CDT SAT MAY 16 1987

...HEAVY THUNDERSTORMS DEVELOPING ACROSS SOUTHEAST SOUTH DAKOTA...

AT 320 PM CDT A NEARLY SOLID LINE OF HEAVY THUNDERSTORMS HAS DEVELOPED
RAPIDLY ACROSS SOUTHEAST SOUTH DAKOTA. THE LINE STRETCHED FROM JUST
NORTH OF PORTER MINNESOTA SOUTHWEST THROUGH BROOKINGS SOUTH DAKOTA TO
JUST EAST OF PICKSTOWN SOUTH DAKOTA. THE HEAVIEST THUNDERSTORMS WERE
LOCATED NEAR BROOKINGS...FREEMAN AND SCOTLAND SOUTH DAKOTA. THE
THUNDERSTORMS WERE MOVING NORTHEAST AROUND 20 MPH.

THESE THUNDERSTORMS WILL CONTINUE TO DEVELOP RAPIDLY DURING THE NEXT FEW
HOURS...THUS PERSONS ACROSS SOUTHEAST SOUTH DAKOTA...NORTLHWEST IOWA
AND SOUTHWEST MINNESOTA ARE UREGED TO KEEP ABREAST OF THE LATEST WEATHER
SITUATION AND BE PREPARED TO TAKE ACTION IF THREATENING WEATHER
APPROACHES.
JANSEN
Special weather statement, May 17, 3:33 PM CDT, 42 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
324 PM CDT SUN MAY 17 1987

...HEAVY THUNDERSTORMS DEVELOPING ACROSS SOUTHEAST SOUTH DAKOTA...

AT 320 PM CDT A NEARLY SOLID LINE OF HEAVY THUNDERSTORMS HAS DEVELOPED
RAPIDLY ACROSS SOUTHEAST SOUTH DAKOTA. THE LINE STRETCHED FROM JUST
NORTH OF PORTER MINNESOTA SOUTHWEST THROUGH BROOKINGS SOUTH DAKOTA TO
JUST EAST OF PICKSTOWN SOUTH DAKOTA. THE HEAVIEST THUNDERSTORMS WERE
LOCATED NEAR BROOKINGS...FREEMAN AND SCOTLAND SOUTH DAKOTA. THE
THUNDERSTORMS WERE MOVING NORTHEAST AROUND 20 MPH.

THESE THUNDERSTORMS WILL CONTINUE TO DEVELOP RAPIDLY DURING THE NEXT FEW
HOURS...THUS PERSONS ACROSS SOUTHEAST SOUTH DAKOTA...TNORTHWEST IOWA
AND SOUTHWEST MINNESOTA ARE UREGED TO KEEP ABREAST OF THE LATEST WEATHER
SITUATION AND BE PREPARED TO TAKE ACTION IF THREATENING WEATHER
APPROACHES.
JANSEN
Special weather statement, May 17, 3:50 PM CDT, 25 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
345 PM CDT SUN MAY 17 1987

...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10 PM CDT
FOR PARTS OF SOUTHEASTERN SOUTH DAKOTA...

AT 330 PM CDT...A LINE OF INTENSE THUNDERSTORMS WITH VERY
HEAVY RAIN HAD DEVELOPED OVER SOUTHEASTERN SOUTH DAKOTA
AND EXTREME WESTERN MINNESOTA.

THE LINE WAS LOCATED ALONG AND 10 MILES EITHER SIDE OF A
LINE FROM 50 MILES EAST OF WATERTOWN...OVER CHIPPEWA COUNTY
IN MINNESOTA TO THE MISSOURI RIVER...35 MILES WEST OF YANKTON.

THE STRONGEST STORMS WERE OVER BON HOMME COUNTY AND YELLOW
MEDICINE COUNTY IN MINNESOTA.

THESE STORMS MAY CONTAIN STRONG GUSTY WINDS...FREQUENT LIGHTNINGj
AND SMALL HA
Special weather statement, May 17, 3:50 PM CDT, 25 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
345 PM CDT SUN MAY 17 1987

...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10 PM CDT
FOR PARTS OF SOUTHEASTERN SOUTH DAKOTA...

AT 330 PM CDT...A LINE OF INTENSE THUNDERSTORMS WITH VERY
HEAVY RAIN HAD DEVELOPED OVER SOUTHEASTERN SOUTH DAKOTA
AND EXTREME WESTERN MINNESOTA.

THE LINE WAS LOCATED ALONG AND 10 MILES EITHER SIDE OF A
LINE FROM 50 MILES EAST OF WATERTOWN...OVER CHIPPEWA COUNTY
IN MINNESOTA TO THE MISSOURI RIVER...35 MILES WEST OF YANKTON.

THE STRONGEST STORMS WERE OVER BON HOMME COUNTY AND YELLOW
MEDICINE COUNTY IN MINNESOTA.

THESE STORMS MAY CONTAIN STRONG GUSTY WINDS...FREQUENT LIGHTNlING
AND SMALL HAIL. PEOPLE IN THE PATHS OF THESE STORMS SHOULD BE

ALERT FOR ANY ADVERSE WEATHER.

MOVEMENT WAS NORTHEAST AT 25 MILES AN HOUR.

EDDY

The office that day

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

IssuedProductOfficeCountiesLasted
May 17, 6:03 PM CDTSevere Thunderstorm WarningFSDBrookings, Lake57 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 1987Every severe thunderstorm warning in 1987

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.