Alert archive / Missouri / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 60, NWS St. Louis, MO

August 20, 1987Adair County, Knox County, Lewis County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Aug 20, 1987, 7:26 PM CDT for Adair County, Knox County, Lewis County, Missouri. It was in force for 49 min. 2 reports 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 20, 1987, 7:26 PM CDT (00:26 UTC)
Expired
Aug 20, 1987, 8:15 PM CDT
In force
49 min
Issued by
NWS St. Louis, MO
Area
Whole counties

Counties Adair County, MO, Knox County, MO, Lewis County, MO

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
Aug 20, 7:35 PM CDTHail 1Knox, MO
Aug 20, 7:45 PM CDTThunderstorm Wind 0Lewis, MO

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, 0.4 hours before the alert went out and 224 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 1987-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1095 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 1987-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 92 square meters per square second.19395878Sfc1 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
1095 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
1543 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
92 m²/s²
0-3 km storm-relative helicity
231 m²/s²
Significant tornado parameter
0.4
Supercell composite
6.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSTL 210025
SVRSTL
MOC001-103-111-210115-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
726 PM CDT THU AUG 20 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL 815 PM CDT FOR THE FOLLOWING COUNTIES OF
 
NORTHEAST MISSOURI... ADAIR... KNOX... SOUTHWESTERN LEWIS
 
RADAR INDICATES A LINE OF SEVERE THUNDERSTORMS FROM JUST NORTHWEST OF
KIRKSVILLE TO 25 MILES EAST OF KIRKSVILLE.  THE THUNDERSTORMS WERE
MOVING TO THE SOUTHEAST AT 30 MPH.
 
PROTECT YOURSELF FROM DAMAGING WINDS...LARGE HAIL AND LIGHTNING
BY STAYING IN A BUILDING...AWAY FROM WINDOWS.  DO NOT USE THE
TELEPHONE OR ELECTRICAL APPLIANCES...EXCEPT IN EMERGENCIES.
 
THIS IS A DANGEROUS STORM.  IF YOU ARE IN ITS PATH YOU SHOULD
PREPARE FOR DAMAGING WIND...LARGE HAIL AND DEADLY LIGHTNING.
 
SLAUGHTER/JOKERST

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 7:52 PM CDTSevere Thunderstorm WarningLSXMarion, Shelby38 min
Aug 20, 8:11 PM CDTTornado WarningLSXMarion19 min
Aug 20, 9:47 PM CDTSevere Thunderstorm WarningLSXLincoln43 min
Aug 20, 9:47 PM CDTSevere Thunderstorm WarningLSXPike33 min
Aug 20, 10:25 PM CDTSevere Thunderstorm WarningLSXSaint Charles35 min

Nearby

Severe Thunderstorm Warnings in Missouri, 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.