Alert archive / Illinois / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 40, NWS Lincoln, IL

June 17, 1990DeKalb County, Illinois

NWS Lincoln, IL issued this severe thunderstorm warning at Jun 17, 1990, 4:31 AM CDT for DeKalb County, Illinois. It was in force for 29 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: Jun 17, 1990, 4:31 AM CDT (09:31 UTC)
Expired: Jun 17, 1990, 5:00 AM CDT
In force: 29 min
Issued by: NWS Lincoln, IL
Area: Whole counties

County DeKalb 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

Time	Report	Where	Remark
Jun 17, 4:45 AM CDT	Thunderstorm Wind 0	De Kalb, 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

Green Bay/Straub, WI (KGRB), launched 00:00Z, 9.5 hours before the alert went out and 293 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 62 J/kg
Mixed-layer CIN: -76 J/kg
Mixed-layer LCL: 875 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 199 m²/s²
0-3 km storm-relative helicity: 258 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KRFD 170931
SVRRFD
ILC037-171000-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING 
NATIONAL WEATHER SERVICE ROCKFORD IL
431 AM CDT SUN JUN 17 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 500 AM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTY

   IN THE NORTH CENTRAL PART OF ILLINOIS
      DEKALB

THIS MORNING AT 435 CDT RADAR WAS SHOWING SEVERE THUNDERSTORMS
MOVING INTO WESTERN DE KALB COUNTY. THESE STORMS WERE MOVING TO THE
EAST AT 40 MILES AN HOUR. THEY WILL PRODUCE WIND GUSTS IN EXCESS
OF 60 MPH.

SOME COMMUNITIES AFFECTED BY THIS SEVERE THUNDERSTORM...
DE KALB...

IF YOU ARE IN AN AREA THREATENED BY THE STORM...GO TO A REINFORECED
SHELpTER.  SEVERE THUNDERSTORMS CAN PRODUCE WINDS OF 60 MPH OR
GREATER...LARGE HAIL...DANGEROUS LIGHTNING AND HEAVY RAIN THAT
CAN QUICKLY FLOOD A LOW LYING AREA.

ATTN: ISP DIST  1..2..16                                FIELDS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 17, 3:53 AM CDT	Severe Thunderstorm Warning	ILX	Lee, Ogle	52 min
Jun 17, 5:12 PM CDT	Severe Thunderstorm Warning	ILX	DeWitt	63 min
Jun 17, 6:07 PM CDT	Tornado Warning	ILX	DeWitt, Piatt	38 min
Jun 17, 6:13 PM CDT	Severe Thunderstorm Warning	ILX	Macon	62 min
Jun 17, 6:13 PM CDT	Severe Thunderstorm Warning	ILX	Macoupin, Montgomery	62 min
Jun 17, 6:21 PM CDT	Severe Thunderstorm Warning	ILX	Christian	69 min
Jun 17, 6:47 PM CDT	Tornado Warning	ILX	Champaign, Piatt	58 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1990 Every severe thunderstorm warning in 1990

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.