Alert archive / Iowa / Severe Thunderstorm Warnings in 1994

Severe Thunderstorm Warning 21, NWS Sioux Falls, SD

June 6, 1994O'Brien County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 6, 1994, 4:30 PM CDT for O'Brien County, Iowa. It was in force for 45 min.

The area

The counties it named.

The facts

Issued
Jun 6, 1994, 4:30 PM CDT (21:30 UTC)
Expired
Jun 6, 1994, 5:15 PM CDT
In force
45 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County O'Brien County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.5 hours before the alert went out and 206 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 1994-06-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1673 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 1994-06-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 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
1673 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
766 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
44 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 
WUUS1 KSUX 062130 RRA
SVRSUX
IAC141-062215-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX CITY IA
430 PM CDT MON JUN 6 1994
 
THE NATIONAL WEATHER SERVICE IN SIOUX CITY HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  515 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN NORTHWEST IOWA
 
   ...NORTHERN OBRIEN COUNTY
 
AT 429 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM 70 MILES NORTHEAST
OF SIOUX CITY IN OSCEOLA COUNTY IOWA. MOVEMENT WAS SOUTH AT 20 MILES AN
HOUR. THE THUNDERSTORM WILL MOVE BETWEEN SANBORN AND HARTLEY IOWA AROUND
5 PM.
 
REMEMBER...SEVERE THUNDERSTORMS CAN PRODUCE DAMAGING WINDS IN EXCESS
OF 60 MPH...LARGE HAIL...DEADLY LIGHTNING...AND HEAVY RAINS THAT CAN
QUICKLY FLOOD LOW LYING AREAS. IF YOU ARE IN THE PATH OF THIS STORM
TAKE SHELTER IN A REINFORCED BUILDING IMMEDIATELY.
 
HOPPES

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 6, 4:33 PM CDTSevere Thunderstorm WarningFSDOsceola57 min
Jun 6, 5:14 PM CDTSevere Thunderstorm WarningFSDO'Brien24 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1994Every severe thunderstorm warning 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.