Alert archive / Iowa / Tornado Warnings in 1986

Tornado Warning 11, NWS Des Moines, IA

June 29, 1986Polk County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 29, 1986, 11:50 PM CDT for Polk County, Iowa. It was in force for 25 min.

The area

The counties it named.

The facts

Issued
Jun 29, 1986, 11:50 PM CDT (04:50 UTC)
Expired
Jun 30, 1986, 12:15 AM CDT
In force
25 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Polk 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, 4.8 hours before the alert went out and 236 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 1986-06-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 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 1986-06-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 119 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
3623 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
119 m²/s²
0-3 km storm-relative helicity
262 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 300450 RRA
TORDSM
IAC153-300515-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1150 PM CDT SUN JUN 29 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 1215 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

CENTRAL IOWA...SOUTHERN POLK

THIS WARNING INCLUDES THE CITY OF DES MOINES.

AT 1140 PM..A TORNADO TOUCHED DOWN IN WEST DES MOINES AT
19TH AND GRAND DEMOLISHING A QUIK TRIP STORE.

THE THUNDERSTORM THAT PRODUCED THE TORNADO WAS MOVING
SOUTHEAST AT AROUND 30 MPH.

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.

HAHN

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, Jun 29, 6:45 PM CDT, 5 hours 5 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
643 PM CDT SUN JUN 29 1986

..A TORNADO WATCH IS IN EFFECT FOR A SMALL PART OF EXTREME NORTHWEST
IOWA UNTIL 10 PM THIS EVENING..

AT 635 PM CDT..
SCATTERED LIGHT SHOWERS HAD DEVELOPED ALONG THE IOWA/MINNESOTA BORDER
BETWEEN SPENCER AND SPIRIT LAKE..MEANWHILE INTENSE THUNDERSTORMS
WHICH HAVE HAD A HISTORY OF PRODUCING LARGE HAIL AND VERY HEAVY RAIN
WERE ENTERING NORTHWEST IOWA.  THE STORM WAS ENTERING PLYMOUTH COUNTY
NEAR THE TOWN OF AKRON..ABOUT 25 MILES NORTH OF SIOUX CITY.

THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 25 TO 30 MILES AN
HOUR.

BARLOW
Special weather statement, Jun 29, 9:21 PM CDT, 2 hours 29 minutes before
<PQ<
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
915 PM CDT SUN JUN 29 1986

THE SEVERE THUNDERSTORM WARNING FOR GREENE COUNTY HAS EXPIRED.
THE STORM HAS DECRESED IN INTENSITY AND^ WAS MOVING SOUTHEAST
AROUND 30 MILES AN HOUR.

FORSTER
Special weather statement, Jun 29, 10:48 PM CDT, 1 hour 2 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1045 PM CDT SUN JUN 29 1986

...SEVERE THUNDERSTORM WATCH FOR A LARGE PART OF SOUTHERN AND CENTRAL
IOWA UNTIL 5 AM MONDAY MORNING...

NO SEVERE WEATHER HAS BEEN REPORTED IN IOWA BETWEEN 1010-1045 PM.

AT 1035 PM...VERY STRONG THUNDERSTORMS WERE OVER WEST CENTRAL AND EAST
CENTRAL IOWA.  ONE STORM WAS JUST WEST OF GUTHRIE CENTER..50 MILES WEST
OF DES MOINES.  ANOTHER STORM WAS JUST EAST OF CEDAR RAPIDS.

VERY HEAVY RAINS..BRIEF GUSTY WINDS AND POSSIBLY SOME SMALL HAIL CAN BE
EXPECTED WITH THESE STORMS.

ELSEWHERE..NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS EXTENDED FROM
NORTHEAST INTO SOUTHWEST I/OWA.  THE LEADING EDGE OF THE RAINFALL
EXTENDED FROM THE QUAD CITIES THROUGH PELLA AND INDIANOLA TO THE SOUTH-
WEST CORNER OF THE STATE.

THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 30 MILES AN HOUR.

SIECZYNSKI
Special weather statement, Jun 29, 11:18 PM CDT, 32 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1115 PM CDT SUN JUN 29 1986

       ...STRONG THUNDERSTORMS APPROACHING DES MOINES...

AT 1105 PM...A NARROW BAND OF VERY STRONG THUNDERSTORMS WAS OVER
CENTRAL IOWA.  THE BAND WAS 15 MILES WIDE AND STRETCHED FROM NEVADA
THROUGH SAYLORVILLE RESERVOIR AND ADEL TO CRESTON.

VERY HEAVY RAINS..FREQUENT DANGEROUS LIGHTNING AND BRIEF GUSTY WINDS
WILL BE EXPERIENCED WITH THE PASSAGE OF THESE STORMS.

BY 1215 AM THIS BAND OF STORMS SHOULD EXTEND FROM NEWTON THROUGH
INDIANOLA TO OSCEOLA.

THE STORMS WERE MOVING SOUTHEAST AT 30 MILES AN HOUR.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR A LARGE PART OF
SOUTHERN AND CENTRALH IOWA UNTIL 5 AM MONDAY MORNING.

SIECZYNSKI
Special weather statement, Jun 29, 11:46 PM CDT, 4 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1145 PM CDT SUN JUN 29 1986

...SEVERE THUNDERSTORM WATCH IN EFFECT FOR A LARGE PART OF
SOUTHERN AND CENTRAL IOWA UNTIL 5 AM MONDAY MORNING...

NO SEVERE WEATHER HAS BEEN REPORTED IN IOWA BETWEEN 1040-1145 PM.

WINDS GUSTS TO 52 MILES AN HOUR WERE RECORDED AT THE DES MOINES
AIRPORT AT 1125 PM.

AT 1135 PM...AN INTENSE THUNDERSTORM WAS IN EAST CENTRAL IOWA JUST
WEST OF IOWA CITY..55 MILES WEST OF THE QUAD CITIES.

OTHER STRONG STORMS WERE OVER CENTRAL AND SOUTHWEST IOWA IN AND AROUND
NEVADA..DES MOINES..ADEL..WINTERSET AND CRESTON.

VERY HEAVY RAINS..FREQUENT LIGHTNING AND WIND GUST BETWEEN 45U AND
50 MILES AN HOUR CAN BE EXPECTED WITH THESE STORMS.

ELSEWHERE NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS EXTENDED
FROM NORTHEAST INTO SOUTHWEST IOWA.

THE SHOWERS AND STORMS WERE MOVNING SOUTHEAST AT 30 MILES AN HOUR.

SIECZYNSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 29, 7:30 PM CDTSevere Thunderstorm WarningDMXCalhoun45 min
Jun 29, 8:26 PM CDTSevere Thunderstorm WarningDMXGreene49 min
Jun 29, 9:00 PM CDTSevere Thunderstorm WarningDMXEmmet45 min
Jun 29, 10:00 PM CDTSevere Thunderstorm WarningDMXGuthrie40 min
Jun 29, 10:18 PM CDTSevere Thunderstorm WarningDMXCass42 min
Jun 29, 10:25 PM CDTFlash Flood WarningDMXDallas, Polk6 hr
Jun 30, 1:12 AM CDTSevere Thunderstorm WarningDMXIowa, Poweshiek48 min
Jun 30, 3:45 AM CDTFlash Flood WarningDMXPolk6 hr

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.