Alert archive / Iowa / Severe Thunderstorm Warnings in 1989

Severe Thunderstorm Warning 21, NWS Sioux Falls, SD

May 23, 1989Osceola County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 23, 1989, 8:22 PM CDT for Osceola County, Iowa. It was in force for 38 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: May 23, 1989, 8:22 PM CDT (01:22 UTC)
Expired: May 23, 1989, 9:00 PM CDT
In force: 38 min
Issued by: NWS Sioux Falls, SD
Area: Whole counties

County Osceola 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

Time	Report	Where	Remark
May 23, 8:35 PM CDT	Thunderstorm Wind 56	Osceola, 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

Minneapolis, MN (KSTC), launched 00:00Z, 1.4 hours before the alert went out and 230 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1041 J/kg
Mixed-layer CIN: -74 J/kg
Mixed-layer LCL: 1374 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 88 m²/s²
0-3 km storm-relative helicity: 267 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 6.8

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KFSD 240123
SVRFSD
IAC143-240200-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
822 PM CDT TUE MAY 23 1989
 
THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  900 PM CDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN NORTHWEST IOWA
          ...EASTERN OSCEOLA
 
SOME CITIES INCLUDED IN THIS WARNING ARE HARRIS AND
OCHEYEDAN IOWA.
 
AT 820 PM CDT RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS
FROM THE WORTHINGTON AREA TO 15 MILES SOUTH/SOUTHWEST OF
WORTHINGTON IN OSCEOLA COUNTY OF NORTHWEST IOWA...NEAR THE
RUSH LAKE AREA. THIS LINE WAS MOVING EAST/SOUTHEAST AT 25 MPH.
 
IF YOU ARE IN THE PATH OF THIS STORM...YOU SHOULD GET TO A
REINFORCED SHELTER. A SEVERE THUNDERSTORM PRODUCES WINDS IN EXCESS
OF 60 MPH...HAIL 3/4 INCH OR LARGER...DEADLY LIGHTNING...AND HEAVY
RAIN THAT CAN QUICKLY FLOOD A LOW LYING AREA.
 
THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE A TORNADO WITH LITTLE
OR NO ADVANCE WARNING SO BE ON THE LOOKOUT.
KAPELA

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 23, 7:27 PM CDT	Severe Thunderstorm Warning	FSD	Lyon	48 min
May 23, 7:27 PM CDT	Severe Thunderstorm Warning	FSD	Osceola	48 min
May 23, 8:07 PM CDT	Tornado Warning	FSD	Lyon, Osceola	38 min
May 23, 8:21 PM CDT	Severe Thunderstorm Warning	FSD	O'Brien	69 min
May 23, 8:37 PM CDT	Severe Thunderstorm Warning	FSD	Sioux	38 min
May 23, 9:29 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee	61 min
May 23, 11:34 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee, Ida	56 min
May 24, 12:32 AM CDT	Severe Thunderstorm Warning	FSD	Ida	28 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1989 Every severe thunderstorm warning 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.