Alert archive / Illinois / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 9, NWS St. Louis, MO

April 30, 1990Randolph County, Illinois; Sainte Genevieve County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 30, 1990, 8:18 PM CDT for Randolph County, Illinois; Sainte Genevieve County, Missouri. It was in force for 42 min.

The area

The counties it named.

The facts

Issued
Apr 30, 1990, 8:18 PM CDT (01:18 UTC)
Expired
Apr 30, 1990, 9:00 PM CDT
In force
42 min
Issued by
NWS St. Louis, MO
Area
Whole counties

Counties Randolph County, IL, Sainte Genevieve County, MO

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

Paducah/Barkley, KY (KPAH), launched 00:00Z, 1.3 hours before the alert went out and 153 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, Paducah/Barkley, KY at 00:00Z on 1990-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Paducah/Barkley, KY at 00:00Z on 1990-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
0 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
180 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSTL 010121
SVRSTL
ILC157-MOC186-010200-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
818 PM CDT MON APR 30 1990
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  900 PM CDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN SOUTHWEST ILLINOIS
          ...RANDOLPH
IN EAST CENTRAL MISSOURI
          ...STE GENEVIEVE
 
AT 815 PM CDT A SEVERE THUNDERSTORM WAS REPORTED IN THE FARMINGTON
AND FLAT RIVER COMMUNITIES IN ST FRANCIS COUNTY IN EAST CENTRAL
MISSOURI.  WINDS TO 70 MPH AND MARBLE SIZED HAIL WERE ALSO REPORTED.
 
 
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.
 
PEDIGO

Nearby

Severe Thunderstorm Warnings in Illinois, 1990Severe Thunderstorm Warnings in Missouri, 1990Every 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; the sounding from the Mesonet's radiosonde archive.