Alert archive / South Dakota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 33, NWS Sioux Falls, SD

July 6, 1987Aurora County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 6, 1987, 7:55 PM CDT for Aurora County, South Dakota. It was in force for 65 min.

The area

The counties it named.

The facts

Issued: Jul 6, 1987, 7:55 PM CDT (00:55 UTC)
Expired: Jul 6, 1987, 9:00 PM CDT
In force: 65 min
Issued by: NWS Sioux Falls, SD
Area: Whole counties

County Aurora 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, 0.9 hours before the alert went out and 132 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2161 J/kg
Mixed-layer CIN: -147 J/kg
Mixed-layer LCL: 1688 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 195 m²/s²
0-3 km storm-relative helicity: 213 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 070055
SVRFSD
SDC003-070200-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
755 PM CDT MON JUL 6 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL  900 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTH CENTRAL SOUTH DAKOTA
          ...AURORA
 
SOME CITIES INCLUDED IN THIS WARNING...WHITE LAKE AND PLANKTINON.
 
AT 755 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM IN BRULE COUNTY
SOUTH DAKOTA...50 MILES WEST OF MITCHELL MOVING EAST AT 20 MPH.
 
AT 751 PM CDT...MARBLE SIZE HAIL AND 50 MPH WIND WERE REPRTED 2 MILES
WEST OF KIMBALL SOUTH DAKOTA.
 
 
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 6, 4:27 PM CDT, 3 hours 28 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HURON SD
425 PM CDT MON JUL 6 1987

AT 420 PM CDT...SCATTERED THUNDERSTORMS WERE DEVELOPING RAPIDLY
OVER CENTRAL SOUTH DAKOTA.  THE STORMS WERE MOSTLY IN EASTERN HUGHES
AND EASTERN SULLY COUNTIES...FROM 25 MILES SOUTHEAST OF PIERRE...
TO 25 MILES NORTHEAST OF PIERRE.

THESE STORMS WILL PRODUCE HAIL...GUSTY WIND...FREQUENT LIGHTNING...
AND VERY HEAVY RAINS.  THE STORMS MAY ALSO DEVELOP ALONG THE
MISSOURI RIVER.  IF YOU ARE IN SULLY...HUGHES...OR HYDE COUNTIES...
OR IF YOU ARE IN RECREATION AREAS ALONG THE MISSOURI...YOU SHOULD
BE PREPARED TO GET TO A PLACE OF SAFETY.   IF YOU ARE BOATING
ON THE MISSOURI RIVER...YOU SHOULD BE PREPARED TO GET OFF.

KRAUSE

Special weather statement, Jul 6, 6:08 PM CDT, 1 hour 47 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
607 PM CDT MON JUL 6 1987

...SEVERE THUNDERSTORM WATCH FOR EASTERN SOUTH DAKOTA
   UNTIL 11 PM CDT...

AT 6 PM CDT NATIONAL WEATER SERVICE RADARS INDICATED AN INTENSE
THUNDERSTORM IN SOUTHEASTERN TODD COUNTY. THIS THUNDERSTORM WAS
MOVING EAST NORTHEAST AT 20 MPH AND WILL BE MOVING INTO WESTERN
TRIPP COUNTY BY 7 PM CDT. STRONG WINDS...SMALL HAIL...HEAVY RAINS
AND DANGEROUS CLOUD TO GROUND LIGHTNING CAN BE EXPECTED WITH THIS
STORM.

PERSONS ACROSS EASTERN TODD AND WESTERN TRIPP COUNTIES INCLUDING
THE COMMUNITIES OF KEYA PAHA AND CLEARFIELD SHOULD KEEP ABREAST
OF THIS WEATHER SITUATION AND BE PREPARED TO GO TO A SAFE PLAGCE
IN THREATENING WEATHER APPROACHES OR IF A WARNING IS ISSUED.
JANSEN

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 6, 7:12 PM CDT	Tornado Warning	FSD	Brule	48 min
Jul 6, 9:34 PM CDT	Severe Thunderstorm Warning	FSD	Davison	26 min
Jul 6, 10:12 PM CDT	Severe Thunderstorm Warning	FSD	Lake, McCook	48 min
Jul 7, 12:33 AM CDT	Severe Thunderstorm Warning	FSD	Lincoln	37 min
Jul 7, 1:01 AM CDT	Tornado Warning	FSD	Union	29 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 1987 Every 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.