Alert archive / Illinois / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 77, NWS Lincoln, IL

September 16, 19874 counties in Illinois

NWS Lincoln, IL issued this severe thunderstorm warning at Sep 16, 1987, 4:50 PM CDT for 4 counties in Illinois. It was in force for 55 min.

The area

The counties it named.

The facts

Issued
Sep 16, 1987, 4:50 PM CDT (21:50 UTC)
Expired
Sep 16, 1987, 5:45 PM CDT
In force
55 min
Issued by
NWS Lincoln, IL
Area
Whole counties

Counties Fulton County, IL, Knox County, IL, McDonough County, IL, Warren 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, 9.8 hours before the alert went out and 70 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 1987-09-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 723 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 1987-09-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 square meters per square second.19395878Sfc1 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
723 J/kg
Mixed-layer CIN
-30 J/kg
Mixed-layer LCL
595 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
69 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KPIA 162150
SVRPIA
ILC187-109-095-057-162245-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PEORIA IL
450 PM CDT WED SEP 16 1987

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

WEST CENTRAL ILLINOIS...SOUTHEAST WARREN...NORTHEAST MCDONOUGH...
 SOUTHWEST KNOX AND NORTHWEST FULTON

AT 440 PM CDT RADAR AND SURFACE REPORTS INDICATED A SEVERE
THUNDERSTORM IN MCDONOUGH COUNTY NEAR MACOMB.  THREE-QUARTER INCH
HAIL WAS REPORTED IN MACOMB WITH THIS STORM.

THE STORM WAS MOVING NORTHEAST AT 30 MILES AN HOUR.

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.

ATTN ISP  DISTRICTS 14 AND 7

NADOLSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 16, 5:50 PM CDTSevere Thunderstorm WarningILXKnox55 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1987Every severe thunderstorm warning 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.