Alert archive / Iowa / Tornado Warnings in 1994

Tornado Warning 7, NWS Sioux Falls, SD

June 20, 1994Woodbury County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Jun 20, 1994, 5:33 PM CDT for Woodbury County, Iowa. It was in force for 27 min.

The area

The counties it named.

The facts

Issued
Jun 20, 1994, 5:33 PM CDT (22:33 UTC)
Expired
Jun 20, 1994, 6:00 PM CDT
In force
27 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Woodbury County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 10.6 hours before the alert went out and 122 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 1994-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1380 joules per kilogram.LCLLFCEL10008507005003002001001 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 1994-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 square meters per square second.1939Sfc1 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
1380 J/kg
Mixed-layer CIN
-117 J/kg
Mixed-layer LCL
1326 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
59 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 KSUX 202232
TORSUX
IAC193-202300-
 
BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX CITY IA
533 PM CDT MON JUN 20 1994
 
THE NATIONAL WEATHER SERVICE IN SIOUX CITY HAS ISSUED A
TORNADO WARNING EFFECTIVE UNTIL  600 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN WEST CENTRAL IOWA
 
   ...CENTRAL WOODBURY COUNTY
 
AT 530 PM A FUNNEL CLOUD WAS REPORTED OVER MOVILLE IOWA...15 MILES EAST
OF SIOUX CITY BY THE IOWA STATE PATROL. MOVEMENT WAS SOUTHEAST AT 25
MILES AN HOUR. PEOPLE IN MOVILLE...LAWTON AND CLIMBING HILL SHOULD
TAKE COVER IMMEDIATELY.
 
THIS IS A DANGEROUS STORM!!  TAKE COVER IMMEDIATELY.  IF YOU ARE
IN A STRONG BUILDING GO TO AN INTERIOR ROOM ON THE LOWEST FLOOR.
ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET
INTO A DITCH OR DEPRESSION...COVER YOUR HEAD WITH YOUR HANDS.
 
 
HUMPHREY
 
&

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 4:59 PM CDTSevere Thunderstorm WarningFSDO'Brien21 min
Jun 20, 5:09 PM CDTTornado WarningFSDPlymouth36 min
Jun 20, 5:42 PM CDTSevere Thunderstorm WarningFSDWoodbury33 min
Jun 20, 6:19 PM CDTSevere Thunderstorm WarningFSDWoodbury26 min

Nearby

Tornado Warnings in Iowa, 1994Every tornado warning in 1994Tornadoes in 1994

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.