Alert archive / Iowa / Tornado Warnings in 1998

Tornado Warning 37, NWS Sioux Falls, SD

June 23, 1998Sioux County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Jun 23, 1998, 8:39 PM CDT for Sioux County, Iowa. It was in force for 31 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jun 23, 1998, 8:39 PM CDT (01:39 UTC)
Expired
Jun 23, 1998, 9:10 PM CDT
In force
31 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Sioux County, IA

The radar

The Sioux Falls radar (KFSD), 72 km from the middle of the area, began a volume at 01:41 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 23, 7:30 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 1.7 hours before the alert went out and 285 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, Minneapolis, MN at 00:00Z on 1998-06-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 901 joules per kilogram.LCLLFCEL10008507005003002001001 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, Minneapolis, MN at 00:00Z on 1998-06-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 212 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
901 J/kg
Mixed-layer CIN
-26 J/kg
Mixed-layer LCL
1105 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
212 m²/s²
0-3 km storm-relative helicity
335 m²/s²
Significant tornado parameter
1.4
Supercell composite
8.6

Open this sounding in Storm Lab

The text

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

167 
WFUS1 KFSD 240141 RRA
TORFSD
IAC167-240210-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
839 PM CDT TUE JUN 23 1998

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHERN SIOUX COUNTY IN NORTHWESTERN IOWA

* UNTIL 910 PM CDT

* AT 837 PM CDT... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A DEVELOPING TORNADO 25 MILES NORTH OF SIOUX CITY  OR 6 MILES
  SOUTHWEST OF MC NALLY MOVING NORTHEAST AT 25 MPH.

* THE TORNADO IS EXPECTED TO BE NEAR...
  MC NALLY                 AROUND 845 PM CDT
  IRETON                   AROUND 900 PM CDT



IF YOU ARE IN THE PATH OF A TORNADO...THE SAFEST PLACE IN A HOME OR
BUSINESS IS AN INTERIOR ROOM ON THE LOWEST FLOOR POSSIBLE.  AVOID
WINDOWS.

THIS IS THE SAME STORM THAT PRODUCED A TORNADO NEAR WESTFIELD AT
833 PM.

MG

&

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 23, 7:19 PM CDTTornado WarningFSDWoodbury31 min
Jun 23, 7:50 PM CDTTornado WarningFSDWoodbury35 min
Jun 23, 8:16 PM CDTTornado WarningFSDWoodbury34 min
Jun 23, 8:18 PM CDTSevere Thunderstorm WarningFSDBuena Vista32 min
Jun 23, 8:23 PM CDTTornado WarningFSDPlymouth32 min
Jun 23, 8:51 PM CDTSevere Thunderstorm WarningFSDWoodbury34 min
Jun 23, 9:20 PM CDTSevere Thunderstorm WarningFSDBuena Vista50 min
Jun 23, 9:55 PM CDTFlash Flood WarningFSDWoodbury3 hr
Jun 24, 1:35 AM CDTFlash Flood WarningFSDWoodbury5 hr

Nearby

Tornado Warnings in Iowa, 1998Every tornado warning in 1998Tornadoes in 1998

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; radar from the NEXRAD Level II archive.