Alert archive / Iowa / Tornado Warnings in 1986

Tornado Warning 16, NWS Des Moines, IA

July 13, 1986Audubon County, Cass County, Iowa

NWS Des Moines, IA issued this tornado warning at Jul 13, 1986, 10:20 PM CDT for Audubon County, Cass County, Iowa. It was in force for 30 min.

The area

The counties it named.

The facts

Issued
Jul 13, 1986, 10:20 PM CDT (03:20 UTC)
Expired
Jul 13, 1986, 10:50 PM CDT
In force
30 min
Issued by
NWS Des Moines, IA
Area
Whole counties

Counties Audubon County, IA, Cass 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, 3.3 hours before the alert went out and 123 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 1986-07-14Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 1986-07-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 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
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 140324
TORDSM
IAC009-029-140350-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1020 PM CDT SUN JUL 13 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 1050 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

SOUTHWEST IOWA...SOUTHERN AUDUBON AND NORTHEAST CASS

AT 1020 PM..DES MOINES WEATHER RADAR NOW INDICATED A TORNADO
ALONG THE AUDUBON..CASS COUNTY LINE..ABOUT 10 MILES SOUTH OF
AUDUBON OR ABOUT 60 MILES WEST OF DES MOINES.

THE STORM WAS MOVING EAST AT 20 TO 25 MPH..AND WILL CONTINUE
TO MOVE EAST ALONG THE CASS..ADAIR COUNTY LINE.

THIS WARNING INCLUDES THE CITY OF 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 SHELTER..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, 2 hours 31 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
Special weather statement, Jul 13, 8:49 PM CDT, 1 hour 31 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
845 PM CDT SUN JUL 13 1986

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

AT 830 PM CDT...
A SEVERE THUNDERSTORM WAS INDICATED IN SOUTHWEST IOWA 35 MILES EAST
OF COUNCIL BLUFFS OR 5 MILES WEST OF ATLANTIC. ONE AND ONE-HALF INCH
HAIL WAS REPORTED FROM THIS STORM AT 815 PM AS IT CROSSED THE CASS
AND POTTAWATTAMIE COUNTY LINE.   THE STORM WAS MOVING EAST AT 15 MILES
AN HOUR AND SHOULD BE IN WESTERN ADAIR COUNTY BY 930 PM.

IN ADDITION TO THE LARGE HAIL..VERY HEAVY RAINS AND HIGH WINDS CAN
BE EXPECTED FROM THIS STORM.  BECAUSE OF THE SLOW MOVEMENT OF THE
STORM LARGE AMOUNTS OF RAIN ARE POSSIBLE OVER CASS AND WESTERN ADAIR
COUNTIES.  PEOPLE IN FLOOD PRONE AREAS SHOULD REMAIN ALERT AND BE
READY TO MOVE QUICKLY AS RAPID RISES IN WATER LEVELS ARE POSSIBLE.

ANOTHER STRONG THUNDERSTORM WAS INDICATED ALONG THE MISSOURI RIVER
15 MIL}ES NORTH OF COUNCIL BLUFFS. THIS STORM WAS MOVING EAST AT
15 MILES AN HOUR.

FERRY

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 13, 7:55 PM CDTSevere Thunderstorm WarningDMXCass65 min
Jul 13, 8:25 PM CDTTornado WarningDMXCass55 min
Jul 13, 9:19 PM CDTSevere Thunderstorm WarningDMXAdair56 min
Jul 13, 9:40 PM CDTSevere Thunderstorm WarningDMXCass35 min
Jul 13, 10:13 PM CDTSevere Thunderstorm WarningDMXAudubon, Cass32 min
Jul 13, 10:36 PM CDTSevere Thunderstorm WarningDMXAdair39 min
Jul 13, 10:41 PM CDTFlash Flood WarningDMXAdair89 min
Jul 13, 11:04 PM CDTSevere Thunderstorm WarningDMXClarke, Madison, Union36 min
Jul 13, 11:40 PM CDTSevere Thunderstorm WarningDMXClarke, Lucas60 min
Jul 14, 12:15 AM CDTSevere Thunderstorm WarningDMXClarke, Decatur, Lucas, Wayne45 min
Jul 14, 12:58 AM CDTSevere Thunderstorm WarningDMXAppanoose, Wayne62 min
Jul 14, 3:00 AM CDTSevere Thunderstorm WarningDMXAdair30 min
Jul 14, 9:18 AM CDTSevere Thunderstorm WarningDMXClay42 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.