Alert archive / Iowa / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 18, NWS Sioux Falls, SD

June 24, 1987Plymouth County, Woodbury County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 24, 1987, 6:37 PM CDT for Plymouth County, Woodbury County, Iowa. It was in force for 68 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jun 24, 1987, 6:37 PM CDT (23:37 UTC)
Expired
Jun 24, 1987, 7:45 PM CDT
In force
68 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

Counties Plymouth County, IA, Woodbury County, IA

The radar

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

What was reported inside it

TimeReportWhereRemark
Jun 24, 6:37 PM CDTThunderstorm Wind 58Woodbury, IA
Jun 24, 7:10 PM CDTThunderstorm Wind 50Woodbury, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.6 hours before the alert went out and 140 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, Omaha, NE at 12:00Z on 1987-06-24Temperature 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, Omaha, NE at 12:00Z on 1987-06-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 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
3614 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
52 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 KSUX 242337
SVRSUX
IAC149-193-250045-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX CITY IA
637 PM CDT WED JUN 24 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL  745 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN NORTHWEST IOWA
          ...PLYMOUTH
IN WEST CENTRAL IOWA
          ...WOODBURY
 
AT 637 PM CDT WINDS GUSTS OF 60 MILES AN HOUR WERE RECORDED AT THE
SIOUX CITY AIRPORT.
 
THESE STORMS WERE MOVING TO THE EAST AT 30 MILES AN HOUR.
 
 
 
 
A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA.  REMEMBER
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES
WITH LITTLE OR NO ADVANCE WARNING.  REMAIN CALM BUT BE ALERT TO
RAPIDLY CHANGING WEATHER CONDITIONS.
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

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, Jun 24, 3:36 PM CDT, 3 hours 1 minute before
^DSMSPSSUX
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
335 PM CDT WED JUN 24 1987

...THUNDERSTORMS FORMING AROUND SIOUXLAND...

AT 330 PM CDT TWO LARGE THUNDERSTORMS WERE BUILDING OVER SOUTHERN
WOODBURY AND NORTHERN MONONA COUNTIES.  MOVEMENT WAS TO THE EAST AT
ABOUT 25 MILES AN HOUR.

THUNDERSTORMS ARE NOW BEGINNING TO BUILD ACROSS THE SIOUXLAND AREA
AND SOME OF THESE STORMS MAY DEVELOP LATER INTO SEVERE THUNDERSTORMS.
PERSONS ACROSS THE SIOUXLAND AREA SHOULD BE ON THE ALERT FOR THE
FORMATION OF SEVERE WEATHER AND TAKE SHELTER IF OBSERVED.  IF ANY
SEVERE WEATHER IS OBSERVED PLEASE RELAY REPORTS TO LOCAL LAW
OR CIVIL DEFENSE AGENCIES FOR RELAY TO THE NATIONAL WEATHER SnERVICE.

SHERLIN
Special weather statement, Jun 24, 3:39 PM CDT, 2 hours 58 minutes before
^DSMSPSSUX
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
335 PM CDT WED JUN 24 1987.........CORRECTION FOR LOCATION...

...THUNDERSTORMS FORMING AROUND SIOUXLAND...

AT 330 PM CDT TWO LARGE THUNDERSTORMS WERE BUILDING OVER SOUTHERN
WOODBURY AND NORTHERN MONONA COUNTIES...ABOUT 20 MILES SOUTH OF
SIOUX CITY.  MOVEMENT WAS TO THE EAST AT ABOUT 25 MILES AN HOUR.

THUNDERSTORMS ARE NOW BEGINNING TO BUILD ACROSS THE SIOUXLAND AREA
AND SOME OF THESE STORMS MAY DEVELOP LATER INTO SEVERE THUNDERSTORMS.
PERSONS ACROSS THE SIOUXLAND AREA SHOULD BE ON THE ALERT FOR THE
FORMATION OF SEVERE WEATHER AND TAKE SHELTER IF OBSERVED.  IF ANY
SEVERE WEATHER IS OBSERVED PLEASE RELAY REPORTSp TO LOCAL LAW
OR CIVIL DEFENSE AGENCIES FOR RELAY TO THE NATIONAL WEATHER SERVICE.

SHERLIN
Special weather statement, Jun 24, 5:12 PM CDT, 1 hour 25 minutes before
^DSMSPSSUX
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
510 PM CDT WED JUN 24 1987

...STRONG THUNDERSTORMS CONTINUE IN MONONA COUNTY IOWA...

AT 500 PM CDT STRONG THUNDERSTORMS CONTINUED IN CENTRAL AND WESTERN
MONONA COUNTY IN IOWA OR 25 MILES SOUTHEAST OF SIOUX CITY. THESE STORMS
CONTINUED TO MOVE TO THE EAST AT 20 MILES AN HOUR. ALSO INTENSE
THUNDERSTORMS CONTINUED IN EASTERN NEBRASKA FROM YANKTON SOUTH DAKOTA TO
JUST WEST OF NORFOLK NEBRASKA TO 15 MILES NORTHWEST OF GRAND ISLAND
NEBRASKA. THESE STORM WERE MOVING TO THE EAST AT 30 MILES AN HOUR.

PERSONS ACROSS THE SIOUXLAND AREA SHOULD BE ON THE ALERT FOR THE
FORMATION OF SEVERE WEATHER AND TAKE SHELTER IF OBSERVED.  IF ANY
SEVERE WEATHER IS OBSERVED PLEASE RELAY REPORTS TO LOCAL LAW ENFORCEMENT
OFFICE OR CIVIL DEFENSE AGENCIES FOR RELAY TO THE NATIONAL WEATHER
SERVICE.
ROSNER
Special weather statement, Jun 24, 5:48 PM CDT, 49 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
535 PM CDT WED JUN 24 1987

AT 530 PM CDT...SCATTERED VERY HEAVY THUNDERSTORMS CONTINUED OVER PARTS
OF SOUTHEAST SOUTH DAKOTA...NORTHEAST NEBRASKA...SOUTHWEST MINNESOTA AND
INTO NORTHWEST IOWA.

THESE STORMS WERE MOSTLY SOUTHEAST OF A LINE FROM CLEAR LAKE TO PICKSTOWN
WITH THE HEAVIEST STORMS LOCATED 15 MILES NORTHEAST AND JUST WEST OF
SIOUX FALLS...10 MILES WEST OF CENTERVILLE AND JUST NORTH OF YANKTON.

THE STORMS OVER THE SOUTHEAST CORNER OF SOUTH DAKOTA COULD PRODUCE VERY
HEAVY RAIN...HAIL AND GUSTY WINDS.  PERSONS IN THE SIOUX FALLS AREA AND
SOUTHWARD INTO THE SOUTHEAST CORNER OF THE STATE SHOULD BE ALERT FOR
THREATENING WEATHER CONDITIONS AS THESE STORMS MOVE THROUGH.

MOVEMENT WAS EAST AT 30 MILES AN HOUR.
PFEIFFER
Special weather statement, Jun 24, 6:01 PM CDT, 36 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
555 PM CDT WED JUN 24 1987

AT 550 PM CDT...SHOWERS AND THUNDERSTORMS...SOME OF THEM INTENSE WITH
VERY HEAVY RAIN...STRONG WINDS AND POSSIBLE HAILL...CONTINUED OVER PARTS
OF SOUTHEAST SOUTH DAKOTA...SOUTHWEST MINNESOTA...NORTHWEST IOWA AND
NORTHEAST NEBRASKA.

THE SHOWERS AND THUNDERSTORMS WERE SCATTERED IN A 100 MILE WIDE AREA
FROM ABOUT 110 MILES SOUTHWEST OF SIOUX FALLS...NEAR MADISON NEBRASKA TO
ABOUT 90 MILES NORTHEAST OF SIOUX FALLS...NEAR GRANITE FALLS MINNESOTA.

THE MOST INTENSE THUNDERSTORMS WERE IN A 25 MILE WIDE AREA FROM 15 MILES
NORTHEAST OF SIOUX FALLS NEAR GARRISON SOUTH DAKOTA TO 75 MILES
SOUTHWEST OF SIOUX FALLS NEAR RANDOLPH NEBRASKA.

PEOPLE THROUGHOUT SOUTHEAST SOUTH DAKOTA...SOUTHWEST MINNESOTA AND
NORTHWEST IOWA SHOULD BE ALERT UNTIL 8 PM CDT FOR INTENSE THUNDERSTORMS
PRODUCING VERY HEAVY RAIN...HAIL AND STRONG GUSTY WINDS OF 40 TO 50 MPH
AT 539 PM CDT THUNDERSTORMS PRODUCED WIND GUSTS OF 47 MPH AT SIOUX
FALLS.
BEHREND
Special weather statement, Jun 24, 6:06 PM CDT, 31 minutes before
^DSMSPSSUX
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
605 PM CDT WED JUN 24 1987

...TORNADO WATCH FOR THE SIOUXLAND AREA UNTIL 1100 PM CDT TONIGHT...

AT 600 PM CDT STRONG THUNDERSTORMS CONTINUED IN MONONA COUNTY IN IOWA.
THESE STORM EXTENDED FROM 40 MILES SOUTHEAST OF SIOUX CITY TO 50 MILES
SOUTH OF SIOUX CITY. THEY WERE MOVING TO THE EAST AT 25 MILES AN HOUR.
INTENSE THUNDERSTORMS CONTINUED IN EASTERN NEBRASKA FROM YANKTON SOUTH
DAKOTA TO 30 MILES WEST OF SIOUX CITY TO JUST WEST OF COLUMBUS NEBRASKA.
THESE STORM WERE MOVING TO THE EAST AT 30 MILES AN HOUR. NO SEVERE
WEATHER HAD BEEN REPORTED IN THE SIOUXLAND AREA AS OF 600 PM CDT.

PERSONS ACROSS THE SIOUXLAND AREA SHOULD BE ON THE ALERT FOR THE
FORMATION OF SEVERE WEATHER AND TAKE SHELTER IF OBSERVED.  IF ANY
SEVERE WEATHER IS OBSERVED PLEASE RELAY REPORTS TO LOCAL LAW ENFORCEMENT
OFFICE OR CIVIL DEFENSE AGENCIES FOR RELAY TO THE NATIONAL WEATHER
SERVICE.]
ROSNER

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 24, 3:11 PM CDTSevere Thunderstorm WarningFSDCherokee91 min
Jun 24, 6:46 PM CDTTornado WarningFSDWoodbury29 min
Jun 24, 6:55 PM CDTSevere Thunderstorm WarningFSDMonona55 min

Nearby

Severe Thunderstorm Warnings in Iowa, 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.