Alert archive / Iowa / Tornado Warnings in 1989

Tornado Warning 26, NWS Des Moines, IA

September 7, 1989Crawford County, Iowa

NWS Des Moines, IA issued this tornado warning at Sep 7, 1989, 8:27 PM CDT for Crawford County, Iowa. It was in force for 33 min.

The area

The counties it named.

The facts

Issued
Sep 7, 1989, 8:27 PM CDT (01:27 UTC)
Expired
Sep 7, 1989, 9:00 PM CDT
In force
33 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Crawford 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, 1.5 hours before the alert went out and 114 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 1989-09-08Temperature 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 1989-09-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 95 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
3627 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
95 m²/s²
0-3 km storm-relative helicity
221 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 080128
TORDSM
IAC047-080200-
 
BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
827 PM CDT THU SEP 7 1989
 
THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A
TORNADO WARNING EFFECTIVE UNTIL  900 PM CDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN WEST CENTRAL IOWA
          ...CRAWFORD
 
AT 820 PM CDT NATIONAL WEATHER SERVICE RADAR IN DES MOINES INDICATED
A VERY STRONG THUNDERSTORM OVER DENISON IN CRAWFORD COUNTY...LOCATED
ABOUT 60 MILES NORTHEAST OF OMAHA.
 
AT 812 PM CDT THE SHERIFF'S OFFICE FOR CRAWFORD COUNTY HAD RECEIVED
A REPORT OF A FUNNEL CLOUD JUST EAST OF DENISON.
 
 
 
IF YOU ARE IN THE PATH OF A TORNADO...THE SAFEST PLACE IS A
BASEMENT.  GET UNDER A WORKBENCH OR PIECE OF STURDY FURNITURE.
IF NO BASEMENT IS AVAILABLE...SEEK SHELTER IN AN INTERIOR ROOM
SUCH AS A CLOSET ON THE LOWEST FLOOR.  USE BLANKETS...PILLOWS...
OR CUSHIONS TO COVER YOUR BODY.  AVOID WINDOWS.
 
DO NOT UzSE YOUR CAR TO TRY TO OUTRUN A TORNADO.  CARS ARE EASILY
TOSSED AROUND BY TORNADO WINDS.  IF YOU ARE CAUGHT IN THE PATH OF
A TORNADO...LEAVE THE CAR AND GO TO A STRONG BUILDING.  IF NO
STRUCTURE IS NEARBY...SEEK SHELTER IN A DITCH OR LOW SPOT.

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, Sep 7, 6:46 PM CDT, 1 hour 41 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
640 PM CDT THU SEP 7 1989

AT 635 PM..AN INTENSE THUNDERSTORM..WITH VERY HEAVY RAINS..WAS LOCATED
IN CENTRAL IOWA JUST EAST OF MARSHALLTOWN...ABOUT 50 MILES NORTHEAST OF
DES MOINES.  VERY HEAVY RAINS...STRONG GUSTY SURFACE WINDS...AND HAIL
MAY ACCOMPANY THE PASSAGE OF THIS STORM.

SCATTERED SHOWERS AND THUNDERSHOWERS WERE ALSO FALLING ON MUCH OF THE
REMAINDER	 OF EAST CENTRAL IOWA.

THE SHOWERS AND THUNDERSTORMS WERE MOVING TO THE EAST AT 30 AN HOUR.

SCOTT

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 10:40 PM CDTSevere Thunderstorm WarningDMXAudubon50 min
Sep 8, 3:38 AM CDTFlash Flood WarningDMXAudubon4 hr

Nearby

Tornado Warnings in Iowa, 1989Every tornado warning in 1989Tornadoes in 1989

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.