Alert archive / Iowa / Tornado Warnings in 1986

Tornado Warning 28, NWS Sioux Falls, SD

July 28, 1986Monona County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Jul 28, 1986, 8:34 PM CDT for Monona County, Iowa. It was in force for 26 min.

The area

The counties it named.

The facts

Issued
Jul 28, 1986, 8:34 PM CDT (01:34 UTC)
Expired
Jul 28, 1986, 9:00 PM CDT
In force
26 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Monona 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 00:00Z, 1.6 hours before the alert went out and 88 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 00:00Z on 1986-07-29Temperature 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 00:00Z on 1986-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 square meters per square second.1939587897Sfc1 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
3613 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
119 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 290135
TORSUX
IAC133-290200-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX CITY IA
834 PM CDT MON JUL 28 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 900 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

WEST CENTRAL IOWA...SOUTHERN MONONA

THIS WARNING INCLUDES THE CITIES OF ONAWA AND KENNEBEC.

AT 829 PM CDT A FUNNEL CLOUD WAS REPORTED NEAR KENNEBEC OR 35 MILES
SOUTHEAST OF SIOUX CITY.

THE STORM WAS MOVING SOUTHEAST AT 25 MILES AN HOUR.

IF YOU ARE IN THE PATH OF THIS TORNADO..GO TO A BASEMENT SHELTER OR
A CENTRAL INTERIOR ROOM ON THE LOWEST FLOOR. ABANDON CARS AND MOBILE
HOMES FOR A REINFORCED BUILDING IF AVAILABLE..IF NOT..LIE IN A
NEARBY DITCH OR DEPRESSION.

THIS IS A DANGEROUS STORM.  TAKE COVER IMMEDIATELY.

PLEASE ASK THE NEAREST LAW ENFORCEMENT AGENCY TO RELAY YOUR
REPORT OF SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE.

ROSNER

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 7:03 PM CDTSevere Thunderstorm WarningFSDOsceola57 min
Jul 28, 7:03 PM CDTSevere Thunderstorm WarningFSDLyon57 min
Jul 28, 7:16 PM CDTTornado WarningFSDSioux29 min
Jul 28, 7:22 PM CDTTornado WarningFSDWoodbury38 min
Jul 28, 7:29 PM CDTSevere Thunderstorm WarningFSDO'Brien61 min
Jul 28, 7:43 PM CDTTornado WarningFSDO'Brien62 min
Jul 28, 8:02 PM CDTSevere Thunderstorm WarningFSDSioux58 min
Jul 28, 8:03 PM CDTTornado WarningFSDMonona, Woodbury27 min
Jul 28, 8:18 PM CDTTornado WarningFSDCherokee47 min
Jul 28, 9:02 PM CDTSevere Thunderstorm WarningFSDMonona58 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; the sounding from the Mesonet's radiosonde archive.