Alert archive / Iowa / Tornado Warnings in 1986

Tornado Warning 9, NWS Omaha, NE

May 12, 1986Mills County, Iowa

NWS Omaha, NE issued this tornado warning at May 12, 1986, 6:30 PM CDT for Mills County, Iowa. It was in force for 30 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
May 12, 1986, 6:30 PM CDT (23:30 UTC)
Expired
May 12, 1986, 7:00 PM CDT
In force
30 min
Issued by
NWS Omaha, NE
Area
Whole counties

County Mills 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
May 12, 6:58 PM CDTThunderstorm Wind 52Mills, 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, 11.5 hours before the alert went out and 70 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 1986-05-12Temperature 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 1986-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 75 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
3615 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
138 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 KOMA 122330
TOROMA
IAC129-130000-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
TORNADO WARNING
NATIONAL WEATHER SERVICE OMAHA NE
630 PM CDT MON MAY 12 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING 
EFFECTIVE UNTIL 700 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

SOUTHWEST IOWA...MILLS

AT 525PM A TORNADO WAS REPORTED ON THE GROUND BY A TRAINED SPOTTER
4 MILES EAST OF GLENWOOD IOWA..ABOUT 25 MILES SOUTHEAST OF OMAHA.
RADAR ALSO INDICATED POSSIBLE TORNADOS ABOUT 10 MILES SOUTH OF
GLENWOOD.

PERSONS IN THE WARNED AREA SHOULD TAKE SHELTER IN A BASEMENT IF
AVAILABLE.  OTHERWISE GO TO A SMALL INTERIOR ROOM ON THE LOWEST
FLOOR.  CARS AND MOBILE HOMES SHOULD BE ABANDONED.

PEOPLE IN THE PATH OF THIS TORNADO SHOULD TAKE COVER IMMEDIATELY
TO SAVE YOUR LIVES.

GAVERS

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 12, 5:07 PM CDTSevere Thunderstorm WarningOAXHarrison, Pottawattamie68 min
May 12, 5:15 PM CDTTornado WarningOAXPottawattamie30 min
May 12, 5:36 PM CDTTornado WarningOAXMills39 min
May 12, 5:50 PM CDTSevere Thunderstorm WarningOAXPottawattamie55 min
May 12, 6:05 PM CDTSevere Thunderstorm WarningOAXMills55 min
May 12, 6:10 PM CDTTornado WarningOAXHarrison35 min
May 12, 6:45 PM CDTSevere Thunderstorm WarningOAXHarrison60 min
May 12, 6:59 PM CDTSevere Thunderstorm WarningOAXMills61 min

Nearby

Tornado Warnings in Iowa, 1986Every tornado warning in 1986Tornadoes in 1986

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.