Alert archive / Illinois / Severe Thunderstorm Warnings in 1993

Severe Thunderstorm Warning 149, NWS St. Louis, MO

August 17, 1993Effingham County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Aug 17, 1993, 6:10 PM CDT for Effingham County, Illinois. It was in force for 50 min.

The area

The counties it named.

The facts

Issued
Aug 17, 1993, 6:10 PM CDT (23:10 UTC)
Expired
Aug 17, 1993, 7:00 PM CDT
In force
50 min
Issued by
NWS St. Louis, MO
Area
Whole counties

County Effingham County, IL

The nearest sounding before it

Paducah/Barkley, KY (KPAH), launched 12:00Z, 11.2 hours before the alert went out and 221 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, Paducah/Barkley, KY at 12:00Z on 1993-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1188 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, Paducah/Barkley, KY at 12:00Z on 1993-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 69 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
1188 J/kg
Mixed-layer CIN
-128 J/kg
Mixed-layer LCL
1127 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
69 m²/s²
0-3 km storm-relative helicity
71 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 KSTL 172311
SVRSTL
ILC049-180000-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
610 PM CDT TUE AUG 17 1993
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  700 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTH CENTRAL ILLINOIS
 
   ...EFFINGHAM COUNTY
 
AT 610 PM..WEATHER SERVICE RADAR INDICATED A SEVERE THUNDERSTORM NEAR
EFFINGHAM.
 
THE STORM WAS DRIFTING SOUTH AT 5 TO 10 MILES AN HOUR...AND WILL BE
AFFECTING THE CITIES OF EFFINGHAM...HEARTVILLE....AND WATSON.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAI$N.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

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 17, 5:51 PM CDT, 19 minutes before
ILZ012-180000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
551 PM CDT TUE AUG 17 1993

...RAPIDLY DEVELOPING THUNDERSTORMS OVER SOUTHEAST ILLINOIS...

AT 550 PM...WEATHER SERVICE RADAR INDICATED A RAPIDLY DEVELOPING
THUNDERSTORM NEAR EFFINGHAM.  ANOTHER THUNDERSTORM WAS ALSO ABOUT 10
MILES NORTH OF EFFINGHAM.

BOTH OF THESE STORMS WERE DRIFTING SOUTH AT 10 MILES AN HOUR...AND WILL
PRODUCE EXTREMELY HEAVY RAINS AND POSSIBLY SOME SMALL HAIL IN THE
EFFINGHAM AREA BETWEEN 550 PM AND 630 PM THIS EVENING.

IN ADDITION...DRIVERS NEAR THE JUNCTIONS OF INTERSTATES 57 AND 70 SHOULD
USE CAUTION...AS HEAVY RAINS WILL BE PRODUCING POOR VISIBILITIES.

TRUETT
Special weather statement, Aug 17, 5:52 PM CDT, 18 minutes before
ILZ012-180000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
551 PM CDT TUE AUG 17 1993

...RAPIDLY DEVELOPING THUNDERSTORMS OVER SOUTHEAST ILLINOIS...

AT 550 PM...WEATHER SERVICE RADAR INDICATED A RAPIDLY DEVELOPING
THUNDERSTORM NEAR EFFINGHAM.  ANOTHER THUNDERSTORM WAS ALSO ABOUT 10
MILES NORTH OF EFFINGHAM.

BOTH OF THESE STORMS WERE DRIFTING SOUTH AT 10 MILES AN HOUR...AND WILL
PRODUCE EXTREMELY HEAVY RAINS AND POSSIBLY SOME SMALL HAIL IN THE
EFFINGHAM AREA BETWEEN 550 PM AND 630 PM THIS EVENING.

IN ADDITION...DRIVERS NEAR THE JUNCTIONS OF INTERSTATES 57 AND 70 SHOULD
USE CAUTION...AS HEAVY RAINS WILL BE PRODUCING POOR VISIBILITIES.

TRUETT

Nearby

Severe Thunderstorm Warnings in Illinois, 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.