Alert archive / Illinois / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 116, NWS St. Louis, MO

June 21, 1997Clinton County, Marion County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jun 21, 1997, 5:44 PM CDT for Clinton County, Marion County, Illinois. It was in force for 46 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
Jun 21, 1997, 5:44 PM CDT (22:44 UTC)
Expired
Jun 21, 1997, 6:30 PM CDT
In force
46 min
Issued by
NWS St. Louis, MO
Area
Whole counties

Counties Clinton County, IL, Marion County, IL

The radar

The St Louis radar (KLSX), 132 km from the middle of the area, began a volume at 22:45 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
Jun 21, 5:45 PM CDTThunderstorm Wind 52Boulder, ILCounty sheriff reported power lines down in Boulder and near Carlyle Lake,
Jun 21, 6:00 PM CDTThunderstorm Wind 52Germantown, ILCounty sheriff reported trees down on the east side of town.
Jun 21, 6:05 PM CDTThunderstorm Wind 65Alma, ILWind gusts estimated at 75 mph downed trees and power lines and caused some roof damage. Much of the roof damage was caused by trees falling on structures.

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 nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 10.7 hours before the alert went out and 176 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 12:00Z on 1997-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3170 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, Lincoln, IL at 12:00Z on 1997-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 187 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
3170 J/kg
Mixed-layer CIN
-37 J/kg
Mixed-layer LCL
624 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
146 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.

025 
WUUS1 KSTL 212246 RRA
SVRSTL
ILC027-121-212330-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
544 PM CDT SAT JUN 21 1997
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  630 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTH CENTRAL ILLINOIS
 
   ...EASTERN CLINTON COUNTY...WESTERN MARION COUNTY
 
AT 544 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS DETECTING A
SEVERE THUNDERSTORM 1 MILE NORTH OF BOULDER ILLINOIS. THE STORMS WAS
MOVING TO THE SOUTHEAST AT 10 MPH. IT WILL MOVE THROUGH THE TOWNS OF
SANDOVEL...FAIRMAN AND ODIN. IT WILL PRODUCE LARGE HAIL AND TORRENTIAL
RAINS.
 
THIS STORM HAS A HISTORY OF DAMAGING HAIL. STAY INSIDE AND AWAY
FROM WINDOWS.
 
GKS/RP

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 4:39 PM CDTSevere Thunderstorm WarningLSXMadison51 min
Jun 21, 5:18 PM CDTSevere Thunderstorm WarningLSXSaint Clair57 min
Jun 21, 5:32 PM CDTSevere Thunderstorm WarningLSXClinton43 min
Jun 21, 6:08 PM CDTSevere Thunderstorm WarningLSXSaint Clair52 min
Jun 21, 6:31 PM CDTSevere Thunderstorm WarningLSXMonroe44 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.