Alert archive / Illinois / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 33, NWS St. Louis, MO

April 19, 1997Clinton County, Saint Clair County, Washington County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 19, 1997, 12:34 AM CDT for Clinton County, Saint Clair County, Washington County, Illinois. It was in force for 41 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 19, 1997, 12:34 AM CDT (05:34 UTC)
Expired: Apr 19, 1997, 1:15 AM CDT
In force: 41 min
Issued by: NWS St. Louis, MO
Area: Whole counties

Counties Clinton County, IL, Saint Clair County, IL, Washington County, IL

The radar

The St Louis radar (KLSX), 98 km from the middle of the area, began a volume at 05:37 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Apr 18, 9:15 PM CDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 5.6 hours before the alert went out and 205 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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.

333 
WUUS1 KSTL 190537 RRA
SVRSTL
ILC027-163-190615-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1234 AM CDT SAT APR 19 1997
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  115 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTH CENTRAL ILLINOIS
 
   ...WESTERN CLINTON COUNTY
 
IN SOUTHWEST ILLINOIS
 
   ...ST. CLAIR COUNTY
 
AT 1234 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED A SEVERE
THUNDERSTORM NEAR COLLINVILLE. THE STORM WAS MOVING SOUTH SOUTHEAST AT
30 MPH. TOWNS IN THE PATH ARE BELLEVILLE...LEBANON AND TRENTON.
 
THIS IS A DANGEROUS STORM BE PREPARED FOR DAMAGING WINDS...HAIL
AND DEADLY LIGHTNING. STAY INSIDE AND AWAY FROM WINDOWS.
 
GKS

1 follow-up statement

328 
WUUS1 KSTL 190536 RRB
SVRSTL
ILC189-190615-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1234 AM CDT SAT APR 19 1997
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  115 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTH CENTRAL ILLINOIS
 
   ...WASHINGTON COUNTY
 
AT 1234 AM CDT RADAR INDICATED A SEVERE THUNDERSTORM JUST NORTHEAST
OF OKAWVILLE MOVING SOUTHEAST AT 30 MPH.
 
RICHVIEW...HOYLETON...AND ASHLEY ARE IN THE PATH OF THIS STORM.
 
THIS STORM WILL LIKELY PRODUCE HAIL AROUND 1 INCH IN DIAMETER
ALONG WITH VERY HEAVY RAIN.
 
JPK

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 18, 8:51 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun	39 min
Apr 18, 8:58 PM CDT	Severe Thunderstorm Warning	LSX	Pike	47 min
Apr 18, 9:45 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun	45 min
Apr 18, 10:20 PM CDT	Severe Thunderstorm Warning	LSX	Madison, Saint Clair	40 min
Apr 18, 11:17 PM CDT	Severe Thunderstorm Warning	LSX	Greene, Jersey, Macoupin, Madison	43 min
Apr 18, 11:56 PM CDT	Severe Thunderstorm Warning	LSX	Jersey, Madison	49 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1997 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.