Alert archive / Iowa / Severe Thunderstorm Warnings in 1993

Severe Thunderstorm Warning 76, NWS Sioux Falls, SD

August 12, 1993Monona County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 12, 1993, 4:48 PM CDT for Monona County, Iowa. It was in force for 27 min.

The area

The counties it named.

The facts

Issued
Aug 12, 1993, 4:48 PM CDT (21:48 UTC)
Expired
Aug 12, 1993, 5:15 PM CDT
In force
27 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Monona County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.8 hours before the alert went out and 88 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 1993-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 59 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 1993-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 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
59 J/kg
Mixed-layer CIN
-246 J/kg
Mixed-layer LCL
1271 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
37 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 122152 RRA
SVRSUX
IAC133-122215-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX CITY IA
448 PM CDT THU AUG 12 1993
 
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 WEST CENTRAL IOWA
 
   ...MONONA COUNTY
 
AT 450 PM CDT A SEVERE THUNDERSTORM WAS LOCATED 5 MILES SOUTHWEST OF
RODNEY...30 MILES SOUTHEAST OF SIOUX CITY. MOVEMENT WAS SOUTHEAST AT 20
MILES AN HOUR. THIS STORM WILL AFFECT CASTANA BY 515 PM.
 
THREE QUARTER INCH HAIL WAS REPORTED BY THE MONONA COUNTY SHERIFF AT 448
PM ALONG HIGHWAY L12 SOUTHEAST OF RODNEY.
 
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.
 
ASK THE NEA|REST LAW ENFORCEMENT AGENCY TO RELAY REPORTS OF SEVERE
WEATHER TO THE NATIONAL WEATHER SERVICE.
 
IRELAND
 
&

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Aug 12, 4:34 PM CDT, 14 minutes before
IAZ013-020-021-031-032-043-NEZ094>096-SDZ066-121400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
435 PM CDT THU AUG 12 1993

...SMALL HAIL POSSIBLE WITH THUNDERSTORMS...

AT 428 PM CDT A THUNDERSTORM POSSIBLY PRODUCING SMALL HAIL WAS LOCATED
NEAR EMERSON NEBRASKA OR 20 MILES SOUTHWEST OF SIOUX CITY. THE STORM
WAS MOVING SOUTHEAST AT 15 MILES AN HOUR. THIS STORM WILL PASS BETWEEN
THURSTON AND WALTHILL AFTER 5 PM AND WILL LIKELY8 CONTINUE TO PRODUCE
SMALL HAIL.

OTHER STORMS WERE LOCATED FROM NORA SOUTH DAKOTA TO CASTANA IOWA. THESE
STORMS MAY BE CAPABLE OF PRODUCING SMALL HAIL AT TIMES.

MICHELS
Special weather statement, Aug 12, 4:35 PM CDT, 13 minutes before
IAZ013-020-021-031-032-043-NEZ094>096-SDZ066-121400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
435 PM CDT THU AUG 12 1993

...SMALL HAIL POSSIBLE WITH THUNDERSTORMS...

AT 428 PM CDT A THUNDERSTORM POSSIBLY PRODUCING SMALL HAIL WAS LOCATED
NEAR EMERSON NEBRASKA OR 20 MILES SOUTHWEST OF SIOUX CITY. THE STORM
WAS MOVING SOUTHEAST AT 15 MILES AN HOUR. THIS STORM WILL PASS BETWEEN
THURSTON AND WALTHILL AFTER 5 PM AND WILL LIKELY CONTINUE TO PRODUCE
SMALL HAIL.

OTHER STORMS WERE LOCATED FROM NORA SOUTH DAKOTA TO CASTANA IOWA. THESE
STORMS MAY BE CAPABLE OF PRODUCING SMALL HAIL AT TIMES.

MICHELS

Nearby

Severe Thunderstorm Warnings in Iowa, 1993Every severe thunderstorm warning in 1993

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.