Alert archive / Iowa / Tornado Warnings in 1986

Tornado Warning 1, NWS Des Moines, IA

April 4, 1986Sac County, Iowa

NWS Des Moines, IA issued this tornado warning at Apr 4, 1986, 4:00 PM CST for Sac County, Iowa. It was in force for 40 min.

The area

The counties it named.

The facts

Issued
Apr 4, 1986, 4:00 PM CST (22:00 UTC)
Expired
Apr 4, 1986, 4:40 PM CST
In force
40 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Sac 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, 10.0 hours before the alert went out and 158 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 1986-04-04Temperature 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 12:00Z on 1986-04-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 97 square meters per square second.19395878Sfc1 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
3586 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
97 m²/s²
0-3 km storm-relative helicity
102 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 042207 COR
TORDSM
IAC161-042240-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING...CORRECTION TO TIMES IN WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
400 PM CST FRI APR 4 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 440 PM CST FOR PEOPLE IN THE FOLLOWING COUNTY OF

WEST CENTRAL IOWA...EASTERN SAC

AT 355 PM..A FUNNEL CLOUD WAS REPORTED 5 TO 10 MILES NORTHWEST OF
CARROLL..ALONG THE SAC-CARROLL COUNTY LINE.   THE STORM WAS MOVING
NORTH AT 35 MILES AN HOUR.

THIS STORM WILL MOVE INTO THE LAKE VIEW AND SAC CITY AREAS BETWEEN
400 AND 430 PM THIS EVENING.

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/BARLOW

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, Apr 4, 2:34 PM CST, 1 hour 26 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
235 PM CST FRI APR 4 1986

...TORNADO WATCH FOR PARTS OF CENTRAL AND WESTERN IOWA UNTIL 8PM...

AT 230 PM...NO SEVERE THUNDERSTORMS WERE INDICATED IN IOWA.  THERE
WERE A FEW SHOWERS AND THUNDERSHOWERS IN THE WEST-CENTRAL PART OF
THE STATE..FROM 30 MILES EAST OF SIOUX CITY..TO 35 MILES NORTHEAST
OF COUNCIL BLUFFS.  THE HEAVIEST THUNDERSHOWER WAS LOCATED IN SHELBY
COUNTY NEAR HARLAN.

THE SHOWERS AND THUNDERSHOWERS WERE MOVING NORTH AT 35 MILES AN HOUR.

BINGHAM
Special weather statement, Apr 4, 3:43 PM CST, 17 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
340 PM CST FRI APR 4 1986

...TORNADO WATCH FOR PARTS OF CENTRAL AND WESTERN IOWA UNTIL 8PM...

AT 330 PM...NO SEVERE THUNDERSTORMS WERE INDICATED IN IOWA.  SHOWERS
AND ISOLATED THUNDERSHOWERS..SOME WITH HEAVY RAINS..WERE DEVELOPING
OVER THE WEST 1/3RD OF IOWA.  THE HEAVIEST THUNDERSHOWERS WERE IN
WEST CENTRAL IOWA..IN THE CARROLL AND DENNISON AREAS.

THEe SHOWERS AND THUNDERSHOWERS WERE MOVING NORTH AT 35 MILES AN
HOUR.  COVERAGE AND INTENSITY HAD SHOWN SOME INCREASE.

BINGHAM/BARLOW

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 4, 4:40 PM CSTTornado WarningDMXSac15 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.