Alert archive / Illinois / Tornado Warnings in 1987

Tornado Warning 8, NWS Lincoln, IL

May 20, 1987Woodford County, Illinois

NWS Lincoln, IL issued this tornado warning at May 20, 1987, 6:34 PM CDT for Woodford County, Illinois. It was in force for 51 min. 2 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
May 20, 1987, 6:34 PM CDT (23:34 UTC)
Expired
May 20, 1987, 7:25 PM CDT
In force
51 min
Issued by
NWS Lincoln, IL
Area
Whole counties

County Woodford County, IL

The radar

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

What was reported inside it

TimeReportWhereRemark
May 20, 6:43 PM CDTTornado F1Woodford, IL
May 20, 7:10 PM CDTThunderstorm Wind 0Woodford, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Peoria Regional, IL (KPIA), launched 12:00Z, 11.6 hours before the alert went out and 35 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 1987-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1840 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, Peoria Regional, IL at 12:00Z on 1987-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.1939Sfc1 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
1840 J/kg
Mixed-layer CIN
-73 J/kg
Mixed-layer LCL
690 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.8

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KPIA 202334
TORPIA
ILC203-210030-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
TORNADO WARNING
NATIONAL WEATHER SERVICE PEORIA IL
634 PM CDT WED MAY 20 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING 
EFFECTIVE UNTIL 730 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

CENTRAL ILLINOIS...CENTRAL AND NORTHEAST WOODFORD

AT 625 PM A PUBLIC REPORT OF A TOUCHDOWN OF A TORNADO 1 MILE
NORTHEAST OF WASHINGTON IN NORTHERN TAZEWELL COUNTY.  CITIES IN
THE PATH OF THIS TORNADO ARE ROANOKE AND BENSON CENTRAL WOODFORD
COUNTY.

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

IF YOU ARE IN AN AREA THREATENED BY THE STORM..GO TO A REINFORCED
SHELTER AND PREPARE FOR DAMAGING WIND...LARGE HAIL...VERY HEAVY
RAIN AND LIGHTNING.

THIS IS A DANGEROUS STORM.  TAKE COVER IMMEDIATELYr.

ATTN ISP  DIST 8

NADOLSKI

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 9:44 AM CDTSevere Thunderstorm WarningILXVermilion31 min
May 20, 5:30 PM CDTSevere Thunderstorm WarningILXStark60 min
May 20, 6:20 PM CDTSevere Thunderstorm WarningILXPeoria35 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.