Alert archive / Illinois / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 32, NWS St. Louis, MO

April 18, 1997Jersey County, Madison County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 18, 1997, 11:56 PM CDT for Jersey County, Madison County, Illinois. It was in force for 49 min. 3 reports 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
Apr 18, 1997, 11:56 PM CDT (04:56 UTC)
Expired
Apr 19, 1997, 12:45 AM CDT
In force
49 min
Issued by
NWS St. Louis, MO
Area
Whole counties

Counties Jersey County, IL, Madison County, IL

The radar

The St Louis radar (KLSX), 56 km from the middle of the area, began a volume at 04:56 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
Apr 19, 12:12 AM CDTHail 1.75Godfrey, IL
Apr 19, 12:14 AM CDTHail 1.75Alton, IL
Apr 19, 12:37 AM CDTHail 0.75Collinsville, IL

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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 18, 9:15 PM CDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 4.9 hours before the alert went out and 187 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, Lincoln, IL at 00:00Z on 1997-04-19Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 1997-04-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 96 square meters per square second.1939587897Sfc1 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
2539 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
96 m²/s²
0-3 km storm-relative helicity
257 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.

144 
WUUS1 KSTL 190458 RRA
SVRSTL
ILC083-119-190545-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1156 PM CDT FRI APR 18 1997
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1245 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHWEST ILLINOIS
 
   ...JERSEY COUNTY...MADISON COUNTY
 
AT 1157 PM A SEVERE THUNDERSTORM WAS 5 MILES SOUTHWEST OF JERSEYVILLE
MOVING SOUTHEAST AT 30 MPH.
 
TOWNS IN THE PATH INCLUDE ALTON AND EDWARDSVILLE.
 
HAIL AROUND 1 INCH IN DIAMETER CAN BE EXPECTED WITH THIS STORM.
 
JPK

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 18, 8:51 PM CDTSevere Thunderstorm WarningLSXCalhoun39 min
Apr 18, 8:58 PM CDTSevere Thunderstorm WarningLSXPike47 min
Apr 18, 9:45 PM CDTSevere Thunderstorm WarningLSXCalhoun45 min
Apr 18, 10:20 PM CDTSevere Thunderstorm WarningLSXMadison, Saint Clair40 min
Apr 18, 11:17 PM CDTSevere Thunderstorm WarningLSXGreene, Jersey, Macoupin, Madison43 min
Apr 19, 12:34 AM CDTSevere Thunderstorm WarningLSXClinton, Saint Clair, Washington41 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1997Every severe thunderstorm warning in 1997

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.