Alert archive / Illinois / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 6, NWS Lincoln, IL
NWS Lincoln, IL issued this severe thunderstorm warning at May 20, 1987, 9:44 AM CDT for Vermilion County, Illinois. It was in force for 31 min.
The area
The counties it named.
The facts
- Issued
- May 20, 1987, 9:44 AM CDT (14:44 UTC)
- Expired
- May 20, 1987, 10:15 AM CDT
- In force
- 31 min
- Issued by
- NWS Lincoln, IL
- Area
- Whole counties
County Vermilion 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, 2.7 hours before the alert went out and 167 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
- 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
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KSPI 201444 SVRSPI ILC183-201515- BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SPRINGFIELD IL 944 AM CDT WED MAY 20 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1015 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF EAST CENTRAL ILLINOIS...EASTERN VERMILION AT 945 AM CST RADAR INDICATED A VERY STRONG THUNDERSTORM NEAR DANVILLE ILLINOIS. THIS THUNDERSTORM WAS MOVING EAST AT 30 MILE AN HOUR. IF YOU ARE IN AN AREA THREATENED BY THE STORM..GO TO A REINFORECED SHELTER AND PREPARE FOR DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN AND LIGHTNING. ATTN ISP DIST...10 GOODSELL
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, May 20, 3:52 AM CDT, 5 hours 52 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PEORIA IL 350 AM CDT WED MAY 20 1987 ...THUNDERSTORMS IN CENTRAL ILLINOIS BETWEEN PEORIA AND MOLINE... AT 345 AM...RADAR INDICATED A 3 TO 5 MILE WIDE BAND OF THUNDERSTORMS IN WEST CENTRAL ILLINOIS FROM 5 MILES SOUTHWEST OF GALESBURG TO 5 MILES WEST OF KEWANEE TO 15 MILES EAST OF MOLINE TO 5 MILES EAST OF DUBUQUE IOWA. THE THUNDERSTORMS WERE MOVING NORTHEAST AT 25 MPH. THEY SHOULD REACH A LINE FROM NEAR STERLING ILLINOIS TO BRADFORD TO ABOUT 20 MILES NORTH OF PEORIA NEAR PRINCEVILLE BY 500 AM. DANGEROUS LIGHTNING..BRIEF GUSTY WINDS TO 45 MPH..SMALL HAIL AND HEAVY RAIN WILL ACCOMPANY THESE THUNDERSTORMS. ATTN ISP DISTS...7..8..AND 17 PALMER
Special weather statement, May 20, 4:55 AM CDT, 4 hours 49 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PEORIA IL 455 AM CDT WED MAY 20 1987 ...SHOWERS AND THUNDERSTORMS CONTINUE IN CENTRAL ILLINOIS... AT 445 AM...RADAR INDICATED THUNDERSTORMS IN NORTH CENTRAL ILLINOIS BETWEEN PEORIA AND MOLINE NORTH TO WEST OF ROCKFORD. THUNDERSTORMS WERE LOCATED FROM KEWANEE TO WYOMING AND TOULON... BETWEEN BRADFORD AND PRINCETON AND FROM 10 MILES SOUTH OF STERLING NORTH INTO SOUTHWEST WISCONSIN. DANGEROUS LIGHTNING...BRIEF GUSTY WIND TO 45 MPH..SMALL HAIL AND HEAVY RAIN CAN BE EXPECTED WITH THESE THUNDERSTORMS. THE THUNDERSTORMS SHOULD MOVE TO A LINE FROM ABOUT MENDOTA TO LA SALLE TO HENRY ILLINOIS BY AROUND 600 AM. THE THUNDERSTORMS WERE IN A LARGER AREA OF RAIN AND SHOWERS THAT EXTENDED FROM BETWEEN DUBUQUE IOWA TO JUST WEST OF ROCKFORD ILLINOIS TO BETWEEN GALESBURG AND CHILLICOTHE JUST BRUSHING NORTHERN PEORIA COUNTY ABOUT 15 MILES NORTH OF PEORIA. ATTN ISP DISTS..7..8..AND 17 PALMER
Special weather statement, May 20, 4:58 AM CDT, 4 hours 46 minutes before
SPECIAL WEATHER STATEMENT..........CORRECTION..... NATIONAL WEATHER SERVICE PEORIA IL 455 AM CDT WED MAY 20 1987 ...SHOWERS AND THUNDERSTORMS CONTINUE IN CENTRAL ILLINOIS... AT 445 AM...RADAR INDICATED THUNDERSTORMS IN NORTH CENTRAL ILLINOIS BETWEEN PEORIA AND MOLINE NORTH TO WEST OF ROCKFORD. THUNDERSTORMS WERE LOCATED FROM KEWANEE TO WYOMING AND TOULON... BETWEEN BRADFORD AND PRINCETON AND FROM 10 MILES SOUTH OF STERLING NORTH INTO SOUTHWEST WISCONSIN. DANGEROUS LIGHTNING...BRIEF GUSTY WIND TO 45 MPH..SMALL HAIL AND HEAVY RAIN CAN BE EXPECTED WITH THESE THUNDERSTORMS. THE THUNDERSTORMS SHOULD MOVE TO A LINE FROM ABOUT MENDOTA TO LA SALLE TO HENRY ILLINOIS BY AROUND 600 AM. THE THUNDERSTORMS WERE IN A LARGER AREA OF RAIN AND SHOWERS THAT EXTENDED FROM BETWEEN DUBUQUE IOWA TO JUST WEST OF ROCKFORD ILLINOIS TO BETWEEN GALESBURG AND CHILLICOTHE JUST BRUSHING NORTHERN PEORIA COUNTY ABOUT 15 MILES NORTH OF PEORIA. THE THUNDERSTORMS AND RAIN WERE MOVING NORTHEAST AT 25 MPH. ATTN ISP DISTS..7..8..AND 17 PALMER
Special weather statement, May 20, 5:56 AM CDT, 3 hours 48 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PEORIA IL 555 AM CDT WED MAY 20 1987 ...THUNDERSTORMS IN CENTRAL ILLINOIS NORTHEAST OF PEORIA... AT 545 AM...A 5 MILE WIDE BAND OF THUNDERSTORMS WAS LOCATED FROM ABOUT 30 MILES NORTHEAST OF PEORIA FROM LACON AND HENRY TO LA SALLE AND NORTH THROUGH ROCKFORD INTO SOUTHERN WISCONSIN. DANGEROUS LIGHTNING..BRIEF WIND GUSTS TO 45 MPH..SMALL HAIL AND HEAVY RAIN WILL ACCOMPANY THESE THUNDERSTORMS. THE BAND OF STORMS WAS MOVING NORTHEAST AT 30 MPH AND SHOULD BE ALONG A LINE FROM BETWEEN ROCKFORD AND CHICAGO TO STREATOR BY AROUND 700 AM. A LARGER AREA OF RAIN AND SOME HEAVY SHOWERS WAS FROM ROCKFORD TO OTTAWA AND STREATOR TO ROANOKE TO CHILLICOTHE TO BRADFORD ILLINOIS AND ON NORTHWEST TO NEAR DUBUQUE IOWA. THE RAIN WAS ALSO MOVING NORTHEAST AT 30 MPH. ATTN ISP DISTS...6..8..AND 17 PALMER
Special weather statement, May 20, 6:56 AM CDT, 2 hours 48 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PEORIA IL 655 AM CDT WED MAY 20 1987 ...THUNDERSTORMS DIMINISH OVER NORTH CENTRAL ILLINOIS... AT 645 AM...RADAR INDICATED AN ISOLATED THUNDERSTORM OVER NORTH CENTRAL ILLINOIS ABOUT 15 MILES SOUTHWEST OF PONTIAC. OTHER THUNDERSTORMS CONTINUED OVER NORTHEAST ILLINOIS BETWEEN JOLIET AND DE KALB AND ON NORTH. A LARGE AREA OF RAIN WITH SOME HEAVIER EMBEDDED SHOWERS EXTENDED FROM JUST WEST OF MILWAUKEE WISCONSIN TO 10 MILES WEST OF JOLIET ILLINOIS TO 25 MILES NORTHEAST OF BLOOMINGTON..NORMAL...THEN BACK NORTHWEST TO BETWEEN PRINCETON AND LA SALLE TO 20 MILES WEST OF ROCKFORD ILLINOIS. THE THUNDERSTORMS AND RAIN WERE MOVING NORTHEAST AT 3 0 MPH. RADAR INDICATED THAT A WIDESPREAD AREA FROM THE MISSISSPI RIVER EAST TO A POINT JUST NORTH OF PEORIA RECIEVED UP TO A HALF INCH OF RAIN IN GENERAL AND OVER ONE INCH IN SCATTERED AREAS. ATTN ISP DISTS...6..8..AND 17 PALMER
The office that day
Everything else NWS Lincoln, IL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 20, 5:30 PM CDT | Severe Thunderstorm Warning | ILX | Stark | 60 min |
| May 20, 6:20 PM CDT | Severe Thunderstorm Warning | ILX | Peoria | 35 min |
| May 20, 6:34 PM CDT | Tornado Warning | ILX | Woodford | 51 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.