Alert archive / Illinois / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 2, NWS Chicago, IL

March 27, 1998LaSalle County, Illinois

NWS Chicago, IL issued this severe thunderstorm warning at Mar 27, 1998, 7:43 PM CST for LaSalle County, Illinois. It was in force for 32 min. 1 report 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
Mar 27, 1998, 7:43 PM CST (01:43 UTC)
Expired
Mar 27, 1998, 8:15 PM CST
In force
32 min
Issued by
NWS Chicago, IL
Area
Whole counties

County LaSalle County, IL

The radar

The Chicago radar (KLOT), 73 km from the middle of the area, began a volume at 01:42 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
Mar 27, 8:00 PM CSTThunderstorm Wind 50Peru, ILWinds to 50 mph were reported at Peru by the Peru police. Strong winds downed power lines and trees.

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
Mar 27, 6:15 PM CSTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.7 hours before the alert went out and 135 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 1998-03-28Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 1998-03-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 223 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
1945 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
223 m²/s²
0-3 km storm-relative helicity
290 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.

932 
WUUS1 KCHI 280144 RRA
SVRCHI
ILC053-099-105-280215-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHICAGO IL
743 PM CST FRI MAR 27 1998
 
THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  815 PM CST
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN EAST CENTRAL ILLINOIS
 
   ...FORD COUNTY
 
IN NORTHEAST ILLINOIS
 
   ...LA SALLE COUNTY...LIVINGSTON COUNTY
 
AT 745 PM CST...A LINE OF STORMS STRETCHES FROM BLOOMINGTON ILLINOIS
NORTHWEST THROUGH CHILLICOTHE AND IS MOVING TO THE NORTHEAST AT 50 MPH.
COMMUNITIES IN THE PATH OF THIS LINE OF STORMS INCLUDE LASALLE...PERU...
STREATOR...PONTIAC...GIBSON CITY...AND PAXTON. EXPECT VERY STRONG WINDS
AS THIS LINE PASSES.
 
THIS STORM HAS A HISTORY OF PRODUCING DAMAGING WINDS.  GO INSIDE
A STURDY BUILDING AND STAY AWAY FROM WINDOWS
 
BRUMER

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, Mar 27, 6:23 PM CST, 1 hour 20 minutes before
ILZ003>006-008-010>014-019>023-032-039-INZ001-280203-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHICAGO IL
623 PM CST FRI MAR 27 1998

...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 1100 PM CST TONIGHT...

THE FIRST SEVERE THUNDERSTORM WATCH OF THE YEAR FOR NORTHEAST ILLINOIS
HAS BEEN ISSUED THIS AFTERNOON. THE FIRST LINE OF SHOWERS STRETCHES
FROM JUST NORTH OF BURLINGTON IOWA TO SPRINGFIELD ILLINOIS AT 615 PM.
THIS LINE WILL REACH A ROCKFORD TO PONTIAC LINE BY 900 PM TONIGHT AND
A MCHENRY TO KANKAKEE LINE BY 1000 PM.

THE MAIN THREAT TONIGHT IS STRONGER WINDS. THE INTENSITY OF THE
WEATHER PATTERN INFLUENCING THE AREA IS STRONG ENOUGH TO ALREADY
PROMPT A HIGH WIND ADVISORY. THIS ADVISES FOR GUSTS TO 45 MPH OR
HIGHER. WITH THE APPROACHING LINE OF STRONG SHOWERS...NO LIGHTNING
ACCOMPANIES THESE SHOWERS TO CALL THEM THUNDERSTORMS...ANY SMALL
DOWNBURST COULD COMBINE WITH THE ADVISORY WINDS TO PRODUCE GUSTS AT OR
ABOVE 60 MPH. WINDS AT THAT STRENGTH CAN DO CONSIDERABLE DAMAGE.

THE SHOWERS ARE LIKELY TO BE OUT OF NORTHEAST ILLINOIS BY 1100 PM CST
TONIGHT.

BRUMER

The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 27, 7:43 PM CSTSevere Thunderstorm WarningLOTFord, Livingston32 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1998Every severe thunderstorm warning in 1998

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.