Alert archive / Illinois / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 47, NWS Lincoln, IL

July 10, 1987Sangamon County, Illinois

NWS Lincoln, IL issued this severe thunderstorm warning at Jul 10, 1987, 6:24 PM CDT for Sangamon County, Illinois. It was in force for 66 min.

The area

The counties it named.

The facts

Issued
Jul 10, 1987, 6:24 PM CDT (23:24 UTC)
Expired
Jul 10, 1987, 7:30 PM CDT
In force
66 min
Issued by
NWS Lincoln, IL
Area
Whole counties

County Sangamon 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, 11.4 hours before the alert went out and 102 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 1987-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1062 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 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 1987-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -68 square meters per square second.1939Sfc1 km3 km6 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
1062 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
762 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-68 m²/s²
0-3 km storm-relative helicity
-62 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSPI 102324
SVRSPI
ILC167-110030-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SPRINGFIELD IL
624 PM CDT FRI JUL 10 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 730 PM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTY OF

CENTRAL ILLINOIS...SOUTHERN SANGAMON

 AT 6 20 PM CDT A LINE OF SEVERE THUNDERSTORMS EXTENDED FROM
SPRINGFIELD ILLINOIS SOUTHWEST TO NEAR GREENFIELD...45 MILES
SOUTHWEST OF SPRINGFIELD.

THE STORMS WERE MOVING SOUTHEAST AT 30 MPH.

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 DANGEROUS LIGHTNING.

REMEMBER...SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
A TORNADO WITH LITTLE OR NO ADVANCE WARNING SO BE ON THE LOOKOUT.

 ATTN ISP DIST...9
 DAVIS

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 10, 2:42 PM CDT, 3 hours 42 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PEORIA IL
235 PM CDT FRI JUL 10 1987

...STRONG THUNDERSTORMS MOVING INTO WEST CENTRAL ILLINOIS...

AT 230 PM CDT THIS FRIDAY AFTERNOON  THE LEADING EDGE OF AN AREA
OF STRONG THUNDERSTORMS WAS LOCATED FROM ABOUT 25 MILES NORTHEAST
OF BURLINGTON IOWA SOUTHWEST THROUGH BURLINGTON TO NEAR KIRKSVILLE
IN NORTHEAST MISSOURI.   THE STORMS WERE MOVING EAST SOUTHEAST
AT ABOUT 25 MPH.

THESE STORMS COULD +PRODUCE VERY HEAVY RAIN...DANGEROUS LIGHTENING
AND STRONG GUSTY SURFACE WINDS.

THEY WILL BE MOVING ACROSS THE WEST CENTRAL ILLINOIS COUNTIES OF
HENDERSON...WARREN AND HANCOCK DURING THE NEXT COUPLE OF HOURS
OR UNTIL ABOUT 430 PM.

ARMBRUST
Special weather statement, Jul 10, 6:08 PM CDT, 16 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SPRINGFIELD IL
6 05 PM CDT FRI JUL 10 1987

AT 6 PM CDT AN AREA OF STRONG THUNDERSTORMS EXTENDED FROM JUST WEST
OF SPRINGFIELD SOUTHWESTWARD TO NEAR WHITEHALL...50 MILES SOUTHWEST
OF SPRINGFIELD.

ANOTHER AREA OF STRONG THUNDERSTORMS WAS LOCATED JUST EAST OF WITT
...45 MILES SOUTHEAST OF SPRINGFIELD...TO NEAR VANDALIA.

THESE STORMS WERE MOVING TO THE EAST SOUTHEAST AT 30 MPH.

THESE STORMS COULD PRODUCE VERY HEAVY RAIN AND STRONG GUSTY WINDS.

DAVIS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 10, 6:31 PM CDTSevere Thunderstorm WarningILXMacoupin59 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.