Alert archive / Iowa / Tornado Warnings in 1990

Tornado Warning 41, NWS Des Moines, IA

June 30, 1990Decatur County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 30, 1990, 4:57 PM CDT for Decatur County, Iowa. It was in force for 33 min. 1 report 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
Jun 30, 1990, 4:57 PM CDT (21:57 UTC)
Expired
Jun 30, 1990, 5:30 PM CDT
In force
33 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Decatur 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

TimeReportWhereRemark
Jun 30, 5:00 PM CDTThunderstorm Wind 50Decatur, 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 12:00Z, 10.0 hours before the alert went out and 226 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 1990-06-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 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 12:00Z on 1990-06-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -5 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
3663 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-5 m²/s²
0-3 km storm-relative helicity
37 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 302157
TORDSM
IAC053-302230-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
TORNADO WARNING 
NATIONAL WEATHER SERVICE DES MOINES IA
457 PM CDT SAT JUN 30 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING 
EFFECTIVE UNTIL 530 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY

   IN THE SOUTH CENTRAL PART OF IOWA
      SOUTHERN DECATUR

AT 455 PM RADAR INDICATED A POSSIBLE TORNADO IN THUNDERSTORM
LOCATED IN THE DECATUR CITY AND DAVIS CITY AREAS...ABOUT
60 MILES SOUTH OF DES MOINES.

THIS STORM WAS MOVING SOUTH AT 25 MILES AN HOUR.

THIS WARNING INCLUDES DECATUR CITY...DAVIS CITY...PLEASANTON
...AND LAMONI.

IF YOU ARE IN THE PATH OF THIS TORNADO...THE SAFEST PLACE IS IN A
BASEMENT.  GET UNDER A WORKBENCH OR PIECE OF STURDY FURNITURE.  IF
NO BASEMENT IS AVAILABLE...SEEK SHELTER IN AN INTERIOR ROOM ON THE
LOWEST FLOOR.  IF YOU ARE IN A VEHICLE OR MOBILE HOME...LEAVE IT AT
ONCE AND TAKE SHELTER IN A REINFORCED BUILDING OR IN A DITCH.

DOWD/TRUETT.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 29, 7:44 PM CDTTornado WarningDMXWright40 min
Jun 30, 8:24 AM CDTSevere Thunderstorm WarningDMXVan Buren36 min
Jun 30, 9:39 AM CDTSevere Thunderstorm WarningDMXVan Buren36 min
Jun 30, 10:20 AM CDTSevere Thunderstorm WarningDMXVan Buren25 min
Jun 30, 1:05 PM CDTFlash Flood WarningDMXDavis, Van Buren4 hr
Jun 30, 1:30 PM CDTSevere Thunderstorm WarningDMXDavis, Van Buren45 min
Jun 30, 2:53 PM CDTSevere Thunderstorm WarningDMXWarren37 min
Jun 30, 3:08 PM CDTSevere Thunderstorm WarningDMXMadison37 min
Jun 30, 3:23 PM CDTSevere Thunderstorm WarningDMXClarke, Lucas37 min
Jun 30, 3:30 PM CDTSevere Thunderstorm WarningDMXWarren30 min
Jun 30, 3:42 PM CDTTornado WarningDMXMadison, Warren33 min
Jun 30, 4:01 PM CDTSevere Thunderstorm WarningDMXClarke, Union44 min
Jun 30, 4:19 PM CDTSevere Thunderstorm WarningDMXDecatur, Wayne41 min
Jun 30, 4:36 PM CDTSevere Thunderstorm WarningDMXDecatur54 min
Jun 30, 4:39 PM CDTSevere Thunderstorm WarningDMXMahaska51 min
Jun 30, 4:42 PM CDTSevere Thunderstorm WarningDMXRinggold, Union48 min
Jun 30, 5:00 PM CDTFlash Flood WarningDMXMahaska4 hr
Jun 30, 5:03 PM CDTTornado WarningDMXAdams, Union27 min

Nearby

Tornado Warnings in Iowa, 1990Every tornado warning in 1990Tornadoes in 1990

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.