Alert archive / Iowa / Severe Thunderstorm Warnings in 1996

Severe Thunderstorm Warning 98, NWS Sioux Falls, SD

July 1, 1996Sioux County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 1, 1996, 4:31 PM CDT for Sioux County, Iowa. It was in force for 49 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
Jul 1, 1996, 4:31 PM CDT (21:31 UTC)
Expired
Jul 1, 1996, 5:20 PM CDT
In force
49 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 21:33 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.

What was reported inside it

TimeReportWhereRemark
Jul 1, 4:45 PM CDTHail 1.75Rock Vly, 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.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.5 hours before the alert went out and 197 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 1996-07-01Temperature 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 1996-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 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
2113 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
38 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 KFSD 012132
SVRFSD
IAC167-012220-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
431 PM CDT MON JUL 1 1996

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS SD HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 520 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN NORTHWEST IOWA

   ...SIOUX COUNTY
 
AT 429 PM CDT...A SEVERE THUNDERSTORM WAS INDICATED BY SIOUX FALLS
DOPPLER RADAR 25 MILES SOUTHEAST OF SIOUX FALLS  OR 10 MILES WEST OF
ROCK VALLEY MOVING EAST AT 25 MPH.

THIS STORM CAN BE EXPECTED IN THE VICINITY OF...
ROCK VALLEY              AROUND 445 PM CDT
CARMEL                   AROUND 455 PM CDT
HULL                     AROUND 455 PM CDT
 
SEVERE THUNDERSTORMS CAN AND DO PRODUCE TORNADOES WITH LITTLE OR NO
ADVANCE WARNING. 

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH...
DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.  FOR YOUR
PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS.

 JCV

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 1, 3:55 PM CDTSevere Thunderstorm WarningFSDLyon45 min
Jul 1, 4:07 PM CDTSevere Thunderstorm WarningFSDPlymouth33 min
Jul 1, 5:09 PM CDTSevere Thunderstorm WarningFSDPlymouth31 min
Jul 1, 5:25 PM CDTSevere Thunderstorm WarningFSDSioux45 min
Jul 1, 5:42 PM CDTSevere Thunderstorm WarningFSDPlymouth43 min
Jul 1, 6:16 PM CDTSevere Thunderstorm WarningFSDWoodbury44 min
Jul 1, 6:23 PM CDTSevere Thunderstorm WarningFSDPlymouth52 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1996Every severe thunderstorm warning in 1996

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; radar from the NEXRAD Level II archive.