Alert archive / Illinois / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 39, NWS Lincoln, IL

July 8, 1986Stephenson County, Winnebago County, Illinois

NWS Lincoln, IL issued this severe thunderstorm warning at Jul 8, 1986, 7:39 PM CDT for Stephenson County, Winnebago County, Illinois. It was in force for 66 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
Jul 8, 1986, 7:39 PM CDT (00:39 UTC)
Expired
Jul 8, 1986, 8:45 PM CDT
In force
66 min
Issued by
NWS Lincoln, IL
Area
Whole counties

Counties Stephenson County, IL, Winnebago 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
Jul 8, 8:25 PM CDTThunderstorm Wind 0Winnebago, 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 00:00Z, 0.7 hours before the alert went out and 187 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 00:00Z on 1986-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1445 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 00:00Z on 1986-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 129 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
1445 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1379 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
129 m²/s²
0-3 km storm-relative helicity
208 m²/s²
Significant tornado parameter
0.3
Supercell composite
7.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KRFD 090039
SVRRFD
ILC177-203-090145-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ROCKFORD IL
739 PM CDT TUE JUL 8 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 845 PM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTIES OF

NORTH CENTRAL ILLINOIS...EASTERN STEPHENSON AND EXTREME WINNEBAGO

 AT 735E PM CST A SEVERE THUNDERSTORM WAS INDICATED BY RADAR NEAR
 ROCK GROVE ILLINOIS WHICH IS 25 NORTHWEST OF ROCKFORD ILLINOIS.
 MOVEMENT WAS EAST AT 25 MPH

 SOME COMMUNITIES WILL BE AFFECTED BY THIS SEVERE THUNDERSTORM...
 GREATER ROCKFORD METRO AREA.. DAKOTA.. ROCKTON

 A SEVERE THUNDERSTORM CAN PRODUCE DAMAGING WINDS OF 60 MPH OR
 OR GREATER.. LARGE HAIL.. DANGEROUS LIGHTNING AND HEAVY RAIN THAT
 CAN QUICKLY FLOOD A LOW LYING AREA.

 THIS IS A SLOW MOVING THUNDERSTORM.. PRODUCING VERY HEAVY RAINS AND
 MAY PRODUCE MINOR FLOODING OF STREAMS.. URBAN AND LOW/ LYING AREAS.

 REPORT SEVERE WEATHER TO LOCAL LAW ENFORCEMENT OFFICIALS AND ASK
 THEM TO RELAY THIS INFORMATION TO THE NATIONAL WEATHER SERVICE.

 ATTN:ISP DIST 16

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, Jul 8, 4:10 PM CDT, 3 hours 29 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SPRINGFIELD IL
409 PM CDT TUE JUL 08 1986

.....SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PARTS OF EASTERN
ILLINOIS UNTIL 9 PM CDT.

AT 405PM CDT WEATHER RADARS SHOWED AN AREA OF SHOWERS AND THUNDER-
STORMS NORTH OF A LINE FROM NEAR RANTOUL,ILLINOIS TO JUST SOUTH
OF DANVILLE,ILLINOIS.

THE STRONGEST THUNDERSTORMS WERE JUST NORTHEAST OF RANTOUL,ILLINOIS
IN CHAMPAIGN COUNTY.

THE AREA OF SHOWERxS AND THUNDERSTORMS WERE MOVING EAST AT 20 MPH.

HILLIARD

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 8, 7:10 PM CDTSevere Thunderstorm WarningILXCarroll20 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1986Every severe thunderstorm warning in 1986

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.