Alert archive / Illinois / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 70, NWS Lincoln, IL
NWS Lincoln, IL issued this severe thunderstorm warning at Aug 16, 1987, 6:15 PM CDT for Stephenson County, Winnebago County, Illinois. It was in force for 45 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
- Aug 16, 1987, 6:15 PM CDT (23:15 UTC)
- Expired
- Aug 16, 1987, 7:00 PM CDT
- In force
- 45 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 16, 6:30 PM CDT | Thunderstorm Wind 0 | Winnebago, 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, 11.3 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.
- Mixed-layer CAPE
- 1711 J/kg
- Mixed-layer CIN
- -92 J/kg
- Mixed-layer LCL
- 818 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 56 m²/s²
- 0-3 km storm-relative helicity
- -15 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.3
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KRFD 162315 SVRRFD ILC177-203-170000- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE ROCKFORD IL 615 PM CDT SUN AUG 16 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 700 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF NORTH CENTRAL ILLINOIS...STEPHENSON AND WINNEBAGO AT 605 PM A LINE OF STRONG THUNDERSTORMS WAS MOVING THROUGH STEPHENSON COUNTY OF NORTHWEST ILLINOIS. TREE AND POWER LINE DAMAGE WAS REPORTED IN LENA ILLINOIS. LENA IS 10 MILES NORTHWEST OF FREEPORT ILLINOIS. THE DAMAGE WAS REPORTED AT 605 PM BY THE STATE POLICE. IF YOU ARE IN AN AREA THREATENED BY THE STORM... GO TO A REINFORECED SHELTER. 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. REPORT SEVERE WEATHER TO POLICE... SHERIFF OR STATE POLICE AND ASK THEM TO RELAY THIS INFORMATION TO THE NATIONAL WEATHER SERVICE.
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, Aug 16, 3:51 PM CDT, 2 hours 24 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PEORIA IL 350 PM CDT SUN AUG 16 1987 ...TORNADO WATCH CONTINUES FOR WEST CENTRAL ILLINOIS... A TORNADO WATCH CONTINUES IN EFFECT UNTIL 1000 PM CDT FOR HENDERSON AND HANCOCK COUNTINES IN WEST CENTRAL ILLINOIS. NO SEVERE WEATHER HAD BEEN REPORTED IN THESE COUNTIES UP UNTIL 345 PM. WARM..UNSTABLE AIR OVER NORTHERN MISSOURI..EASTERN IOWA AND WESTERN ILLINOIS WAS AHEAD OF A COLD FRONT MOVING EAST THROUGH IOWA. THIS CONDITION COULD SEE A RAPID DEVELOPEMENT OF THUNDERSTORMS OVER WEST CENTRAL ILLINOIS BETWEEN 400 PM AND 600 PM. KEEP AN EYE ON THE SKY FOR THUNDERSTORM DEVELOPEMENT AND WATCH TELEVISION OR LISTEN TO RADIO FOR ADDITIONAL STATsEMENTS AND POSSIBLE WARNINGS. PALMER ATTN ISP DIST 14
Special weather statement, Aug 16, 5:42 PM CDT, 33 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PEORIA IL 540 PM CDT SUN AUG 16 1987 ...THUNDERSTORMS APPROACHING WEST CENTRAL ILLINOIS SOUTH OF BURLINGTON IOWA... AT 535 PM..RADAR INDICATED A RAPIDLY DEVELOPING BAND OF THUNDERSTORMS IN AN AREA FROM KIRKSVILLE MISSOURI TO OTTUMA IOWA TO BURLINGTON IOWA AND BACK TO KIRKSVILLE. THE BAND OF STORMS WAS MOVING EAST AT ABOUT 20 TO 25 MPH TOWARD THE MISSISSIPPI RIVER AND SHOULD BE EDGING INTO WESTERN ILLINOIS BY AROUND 630 PM. HANCOCK AND HENDERSON COUNTIES IN WEST CENTRAL ILLINOIS ARE IN A TORNADO WATCH UNTIL 1000 PM CDT. PEOPLE IN THESE COUNTIES SHOULD STAY ALERT FOR THE APPROACH OF THESE THUNDERSTORMS AND HAVE A PLAN OF SAFETY IN MIND SHOULD YOU NEED TO QUICKLY MOVE TO A SUBSTANTIAL SHELTER. THESE STORMS WILL BRING DANGEROUS LIGHTNING..POSSIBLE BRIEF GUSTY WINDS TO 50 MPH..HAIL AND HEAVY RAIN. PALMER ATTN ISP DIST 14
The office that day
Everything else NWS Lincoln, IL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 16, 6:38 PM CDT | Severe Thunderstorm Warning | ILX | Carroll | 52 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.