Alert archive / Iowa / Tornado Warnings in 1987

Tornado Warning 3, NWS Sioux Falls, SD

June 24, 1987Woodbury County, Iowa; Dakota County, Nebraska

NWS Sioux Falls, SD issued this tornado warning at Jun 24, 1987, 6:46 PM CDT for Woodbury County, Iowa; Dakota County, Nebraska. It was in force for 29 min. 1 report 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, 6:46 PM CDT (23:46 UTC)
Expired
Jun 24, 1987, 7:15 PM CDT
In force
29 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

Counties Woodbury County, IA, Dakota County, NE

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, 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, 11.8 hours before the alert went out and 119 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 KDSM 242351 COR
TORSUX
IAC193-NEC043-250015-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING  ....CORRECTION....
NATIONAL WEATHER SERVICE SIOUX CITY IA
646 PM CDT WED JUN 24 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 715 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

WEST CENTRAL IOWA...
 WESTERN WOODBURY
NORTHEAST NEBRASKA...
 EASTERN DAKOTA

AT 642 PM CDT A TORNADO WAS REPORTED ON THE GROUND AT ATOKAD PARK
5 MILES SOUTHWEST OF SIOUX CITY IOWA.

THIS STORM WAS MOVONG TO THE EAST AT 30 MILES AN HOUR.

IF A TORNADO APPROACHES...TAKE COVER IMMEDIATELY.  A BASEMENT...
INTERIOR HALLWAY...OR A ROOM ON THE LOWEST FLOOR IS THE SAFEST
PLACE IN MOST BUILDINGS.  IF YOU ARE IN A MOBILE HOME OR AN
AUTOMOBILE...LEAVE AT ONCE.  TAKE COVER IN A STORM SHELTER...OR LIE
IN A NEARBY DITCH OR DEPRESSION.

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, 6:37 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury68 min
Jun 24, 6:55 PM CDTSevere Thunderstorm WarningFSDMonona55 min

Nearby

Tornado Warnings in Iowa, 1987Tornado Warnings in Nebraska, 1987Every tornado warning in 1987Tornadoes 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.