Alert archive / Iowa / Tornado Warnings in 1987

Tornado Warning 4, NWS Des Moines, IA

June 20, 1987Wayne County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 20, 1987, 4:45 PM CDT for Wayne County, Iowa. It was in force for 18 min.

The area

The counties it named.

The facts

Issued
Jun 20, 1987, 4:45 PM CDT (21:45 UTC)
Expired
Jun 20, 1987, 5:03 PM CDT
In force
18 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Wayne County, IA

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

Omaha, NE (KOAX), launched 12:00Z, 9.8 hours before the alert went out and 263 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 1987-06-20Temperature 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 1987-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -2 square meters per square second.193958Sfc1 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
3606 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-2 m²/s²
0-3 km storm-relative helicity
-7 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 202148
TORDSM
IAC185-202245-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
445 PM CDT SAT JUN 20 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 530 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

SOUTH CENTRAL IOWA...
 WAYNE

AT 445 PM...A FUNNEL CLOUD WAS REPORTED OVER CENTRAL WAYNE COUNTY
NEAR ALLERTON...SOME 30 MILES NORTHEAST OF LAMONI.

RADAR INDICATED THE STORM WAS MOVING VERY LITTLE.

TOWNS NEAR THIS STORM ARE ALLERTON AND CORYDON.

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.

TRUETT

Nearby

Tornado Warnings in Iowa, 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; the sounding from the Mesonet's radiosonde archive.