Alert archive / Illinois / Tornado Warnings in 1987

Tornado Warning 5, NWS Lincoln, IL

April 11, 1987Champaign County, Piatt County, Illinois

NWS Lincoln, IL issued this tornado warning at Apr 11, 1987, 5:10 PM CDT for Champaign County, Piatt County, Illinois. It was in force for 35 min.

The area

The counties it named.

The facts

Issued
Apr 11, 1987, 5:10 PM CDT (22:10 UTC)
Expired
Apr 11, 1987, 5:45 PM CDT
In force
35 min
Issued by
NWS Lincoln, IL
Area
Whole counties

Counties Champaign County, IL, Piatt County, IL

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Peoria Regional, IL (KPIA), launched 12:00Z, 10.2 hours before the alert went out and 122 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, Peoria Regional, IL at 12:00Z on 1987-04-11Temperature 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, Peoria Regional, IL at 12:00Z on 1987-04-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1952 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
116 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 KSPI 112212 RRA
TORSPI
ILC147-019-112245-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SPRINGFIELD IL
510 PM CDT SAT APR 11 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 545 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

EAST CENTRAL ILLINOIS...PIATT AND CHAMPAIGN

AT 5 03 PM CDT A TORNADO WAS REPORTED ON THE GROUND  NEAR DELAND
ILLINOIS IN PIATT COUNTY. A TORNADO WAS ALSO REPORTED ON THE GROUND
NEAR WELDON ILLINOIS ON THE DE-WITT AND PIATT COUNTY LINE.

THE THUNDERSTORMS PRODUCING THESE TORNADOS WERE MOVING EAST AT 25
MPH.

IF YOU ARE IN THE PATH OF THIS TORNADO...YOU SHOULD GO TO A
BASEMENT SHELTER IF AVAILABLE	. OTHERWISE GO TO A CENTRAL INTERIOR
ROOM ON THE LOWEST FLOOR POSSIBLE. ABANDON CARS AND MOBIL HOMES
FOR A REINFORCED BUILDING.

 ATTN ISP DIST...10
 HILLIARD

What forecasters said that day

The local office's own words before this tornado 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, Apr 11, 3:07 PM CDT, 2 hours 3 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PEORIA IL
305 PM CDT SAT APR 11 1987

A LINE OF HEAVY THUNDERSTORMS HAD DEVELOPED OVER NORTH CENTRAL
ILLINOIS FROM MOLINE EXTENDING SOUTHEAST TO CANTON...AND WERE
MOVING NORTHEAST AT 35 MPH.

A FEW OF THESE THUNDERSTORMS COULD BE ACCOMPANIED WITH BRIEF PEROIDS
OF HEAVY DOWNPOURS...SOME SMALL HAIL AND STRONG GUSTY SURFACE WINDS.

AT 230 PM CDT SMALL HAIL WAS REPORTED IN THE GALESBURG AREA.

ATTN4 ISP 6 8 17

STUMETZ

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 11, 3:51 PM CDTTornado WarningILXPeoria, Woodford69 min
Apr 11, 4:05 PM CDTSevere Thunderstorm WarningILXDeWitt, Piatt55 min
Apr 11, 4:27 PM CDTTornado WarningILXDeWitt, Logan33 min
Apr 11, 4:42 PM CDTTornado WarningILXMacon, Piatt33 min
Apr 11, 4:42 PM CDTTornado WarningILXChampaign33 min

Nearby

Tornado Warnings in Illinois, 1987Every tornado warning in 1987Tornadoes in 1987

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.