Alert archive / South Dakota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 110, NWS Sioux Falls, SD

July 23, 1987Aurora County, Davison County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 23, 1987, 7:19 PM CDT for Aurora County, Davison County, South Dakota. It was in force for 56 min.

The area

The counties it named.

The facts

Issued
Jul 23, 1987, 7:19 PM CDT (00:19 UTC)
Expired
Jul 23, 1987, 8:15 PM CDT
In force
56 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

Counties Aurora County, SD, Davison 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 00:00Z, 0.3 hours before the alert went out and 134 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 1987-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3000 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 1987-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 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
3000 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
1575 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
144 m²/s²
Significant tornado parameter
0.8
Supercell composite
10.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KFSD 240019
SVRFSD
SDC003-035-240115-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
719 PM CDT THU JUL 23 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL  815 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN SOUTH CENTRAL SOUTH DAKOTA
          ...NORTHERN AURORA
IN SOUTHEAST SOUTH DAKOTA
          ...NORTHERN DAVISON
 
SOME CITIES INCLUDED IN THIS WARNING...MITCHELL...PLANKINTON.
 
AT 715 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM IN NORTHERN
AURORA COUNTY JUST NORTH OF PLANKINTON SOUTH DAKOTA MOVING EAST AT 30
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.
 
THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE A TORNADO WITH LITTLE
OR NO ADVANCE WARNING SO BE ON THE LOOKOUT.
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, Jul 23, 1:45 PM CDT, 5 hours 34 minutes before
RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
140 PM CDT THU JUL 23 1987

...A TORNADO WATCH IS IN EFFECT FROM 145PM CDT UNTIL 9 PM CDT
FOR PORTIONS OF EASTERN SOUTH DAKOTA...

AT 125 PM CDT...WIDELY SCATTERED THUNDERSTORMS WERE LOCATED
OVER PARTS OF SOUTH EAST CENTRAL AND SOUTHEAST SOUTH DAKOTA.

THE THUNDERSTORMS WERE OCCURRING OVER PARTS OF DAVISON...
NORTHERN HANSON AND SOUTHERN MINER COUNTIES.

MOVEMENT WAS EAST AT 25 MILES AN HOUR.

MJILLER
Special weather statement, Jul 23, 1:47 PM CDT, 5 hours 32 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
140 PM CDT THU JUL 23 1987

...A TORNADO WATCH IS IN EFFECT FROM 145PM CDT UNTIL 9 PM CDT
FOR PORTIONS OF EASTERN SOUTH DAKOTA...

AT 125 PM CDT...WIDELY SCATTERED THUNDERSTORMS WERE LOCATED
OVER PARTS OF SOUTH EAST CENTRAL AND SOUTHEAST SOUTH DAKOTA.

THE THUNDERSTORMS WERE OCCURRING OVER PARTS OF DAVISON...
NORTHERN HANSON AND SOUTHERN MINER COUNTIES.

MOVEMENT NWAS EAST AT 25 MILES AN HOUR.

MILLER
Special weather statement, Jul 23, 2:34 PM CDT, 4 hours 45 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
235 PM CDT THU JUL 23 1987

...A TORNADO WATCH IS IN EFFECT UNTIL 9 PM CDT
FOR PORTIONS OF EASTERN SOUTH DAKOTA...

AT 225 PM CDT...WIDELY SCATTERED SHOWERS WERE OCCURRING OVER PARTS
OF EXTREME EASTERN SOUTH DAKOTA...WHILE NORTHEAST NEBRASKA HAD
WIDELY SCATTERED THUNDERSTORMS WITH HEAVY RAIN.

IN SOUTH DAKOTA THE SHOWERS WERE LOCATED FROM NEAR HOWARD...25 MILES
NORTHWEST OF MITCHELL NORTHEAST TO ABOUT 10 MILES EAST OF CLEAR LAKE
...OR ABOUT 25 MILES NORTHEAST OF BROOKINGS. THE THUNDERSTORMS THAT
WERE IN NEBRASKA WERE ABOUT 10 MILES SOUTH OF BONESTEEL

MOVEMENT WAS EAST AT 15 MILES AN HOUR.

MILLER
Special weather statement, Jul 23, 3:36 PM CDT, 3 hours 43 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
335 PM CDT THU JUL 23 1987

...A TORNADO WATCH IS IN EFFECT UNTIL 9 PM CDT
FOR PORTIONS OF EASTERN SOUTH DAKOTA...

AT 325 PM CDT...WIDELY SCATTERED THUNDERSTORMS AND SHOWERS WERE
OCCURRING OVER PARTS OF EXTREME SOUTH CENTRAL SOUTH DAKOTA.

IN SOUTH DAKOTA THE SHOWERS WERE LOCATED OVER SOUTHERN CHARLES MIX AND
GREGORY COUNTIES OR SOUTH OF A BONESTEEL/ARMOUR LINE.

MOVEMENT WAS EAST AT 15 MILES AN HOUR.

MILLER
Special weather statement, Jul 23, 5:20 PM CDT, 1 hour 59 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
515 PM CDT THU JUL 23 1987

...TORNADO WATCH UNTIL 9 PM CDT FOR A LARGE PORTION OF SOUTH DAKOTA
AND SOUTHWEST MINNESOTA...

AT 510 PM CDT RADAR INDICATED ONLY LIGHT RAIN SHOWERS ACROSS DOUGLAS
COUNTY OF SOUTHEAST SOUTH DAKOTA. THESE SHOWERS CONTINUE TO WEAKEN
AS THEY MOVED EAST.
<
HOWEVER...THUNDERSTORMS ARE EXPECTED TO REDEVELOP OVER THE WATCH AREA
TONIGHT AS AN UPPER LEVEL DISTURBANCE MOVES ACROSS SOUTH DAKOTA.
AT 510 PM THUNDERSTORMS HAD BEGUN TO DEVELOP OVER WESTERN SOUTH DAKOTA
WITH THIS DISTURBANCE. PERSONS ACROSS EASTERN SOUTH DAKOTA...SOUTHWEST
MINNESOTA AND NORTHWEST IOWA SHOULD KEEP ABREAST OF THIS WEATHjER
SITUATION BY LISTENING TO NOAA WEATHER RADIO...LOCAL RADIO OR
TELEVISION FOR LATER STATEMENTS OR POSSIBLE WARNINGS.
JANSEN

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 7:08 PM CDTSevere Thunderstorm WarningFSDMellette, Todd67 min
Jul 24, 2:26 PM CDTSevere Thunderstorm WarningFSDYankton64 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.