Alert archive / Iowa / Tornado Warnings in 1986

Tornado Warning 15, NWS Des Moines, IA

July 13, 1986Cass County, Iowa

NWS Des Moines, IA issued this tornado warning at Jul 13, 1986, 8:25 PM CDT for Cass County, Iowa. It was in force for 55 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: Jul 13, 1986, 8:25 PM CDT (01:25 UTC)
Expired: Jul 13, 1986, 9:20 PM CDT
In force: 55 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Cass 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

Time	Report	Where	Remark
Jul 13, 8:45 PM CDT	Hail 1.5	Cass, IA
Jul 13, 9:25 PM CDT	Hail 1.75	Cass, 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 00:00Z, 1.4 hours before the alert went out and 120 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3607 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 46 m²/s²
0-3 km storm-relative helicity: 182 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 140126
TORDSM
IAC029-140220-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
825 PM CDT SUN JUL 13 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 920 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

SOUTHWEST IOWA...NORTHERN CASS

AT 823 PM..DES MOINES WEATHER RADAR INDICATED A TORNADO IN
EXTREME NORTHWEST CASS COUNTY NEAR MARNE..JUST A FEW MILES WEST
OF ATLANTIC..OR ABOUT 40 MILES NORTHEAST OF COUNCIL BLUFFS.

THE STORM WAS MOVING EAST AT 10 TO 15 MILES AN HOUR.

ALL PEOPLE IN THE ATLANTIC AREA SHOULD TAKE COVER AT ONCE.

THIS WARNING INCLUDES ATLANTIC AND MARNE..AS WELL AS WIOTA AND
ANITA.

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 SHqELTER..OR LIE IN A NEARBY
DITCH OR DEPRESSION.

FERRY/TRUETT

What forecasters said that day

The local office's own words before this tornado 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, Jul 13, 7:49 PM CDT, 36 minutes before

RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
740 PM CDT SUN JUL 13 1986

...FLASH FLOOD WATCH TONIGHT FOR SOUTHWEST AND SOUTH CENTRAL IOWA...

...THUNDERSTORM DEVELOPS IN SOUTHWEST IOWA...

AT 730 PM CDT...
A STRONG THUNDERSTORM HAD DEVELOPED OVER SOUTHWEST IOWA...25 MILES
EAST OF COUNCIL BLUFFS NEAR OAKLAND.  THIS STORM WILL PRODUCE
BRIEF HEAVY RAINS AS IT MOVES EAST AT 20 MILES AN HOUR.  THE STORM
SHOULD BE SOUTH OF ATLANTIC BY 83I0 PM.

AN INTENSE THUNDERSTORM WAS LOCATED IN EAST CENTRAL NEBRASKA ABOUT
35 MILES NORTHWEST OF COUNCIL BLUFFS.  THIS STORM WAS ALSO MOVING
EAST AT 20 TO 25 MILES AN HOUR AND SHOULD CROSS THE IOWA BORDER
SOUTH OF MONDAMIN BY 830 PM.

FERRY

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 13, 7:55 PM CDT	Severe Thunderstorm Warning	DMX	Cass	65 min
Jul 13, 9:19 PM CDT	Severe Thunderstorm Warning	DMX	Adair	56 min
Jul 13, 9:40 PM CDT	Severe Thunderstorm Warning	DMX	Cass	35 min
Jul 13, 10:13 PM CDT	Severe Thunderstorm Warning	DMX	Audubon, Cass	32 min
Jul 13, 10:20 PM CDT	Tornado Warning	DMX	Audubon, Cass	30 min
Jul 13, 10:36 PM CDT	Severe Thunderstorm Warning	DMX	Adair	39 min
Jul 13, 10:41 PM CDT	Flash Flood Warning	DMX	Adair	89 min
Jul 13, 11:04 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Madison, Union	36 min
Jul 13, 11:40 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas	60 min
Jul 14, 12:15 AM CDT	Severe Thunderstorm Warning	DMX	Clarke, Decatur, Lucas, Wayne	45 min
Jul 14, 12:58 AM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Wayne	62 min
Jul 14, 3:00 AM CDT	Severe Thunderstorm Warning	DMX	Adair	30 min
Jul 14, 9:18 AM CDT	Severe Thunderstorm Warning	DMX	Clay	42 min

Nearby

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