Alert archive / Illinois / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 65, NWS St. Louis, MO

April 20, 1999Calhoun County, Pike County, Illinois; Pike County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 20, 1999, 11:56 PM CDT for Calhoun County, Pike County, Illinois; Pike County, Missouri. It was in force for 49 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
Apr 20, 1999, 11:56 PM CDT (04:56 UTC)
Expired
Apr 21, 1999, 12:45 AM CDT
In force
49 min
Issued by
NWS St. Louis, MO
Area
Whole counties

Counties Calhoun County, IL, Pike County, IL, Pike County, MO

What was reported inside it

TimeReportWhereRemark
Apr 21, 12:05 AM CDTHail 0.75Bowling Green, 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 20, 9:15 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 4.9 hours before the alert went out and 215 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, Lincoln, IL at 00:00Z on 1999-04-21Temperature 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, Lincoln, IL at 00:00Z on 1999-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 347 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
1165 m above ground
0-6 km bulk shear
68 kt
0-1 km storm-relative helicity
347 m²/s²
0-3 km storm-relative helicity
657 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 KSTL 210456 RRA
SVRSTL
ILC013-149-MOC163-210545-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1156 PM CDT TUE APR 20 1999

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN CALHOUN COUNTY IN SOUTHWESTERN ILLINOIS
  PIKE COUNTY ILLINOIS IN WEST CENTRAL ILLINOIS
  EASTERN PIKE COUNTY MISSOURI IN NORTHEASTERN MISSOURI

* UNTIL 1245 AM CDT

* AT 1155 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM JUST EAST OF BOWLING GREEN MISSOURI... MOVING
  EAST NORTHEAST AT 30 MPH.

* LOCATIONS THAT WILL BE AFFECTED...
  CLARKSVILLE MO
  PLEASANT HILL IL



THE PRIMARY SEVERE FWEATHER THREAT IS DAMAGING HAIL. LARGE HAIL CAN
CAUSE EXTENSIVE PROPERTY DAMAGE AN SERIOUS INJURY TO PEOPLE CAUGHT
OUTDOORS. MOVE INSIDE A STURDY BUILDING IMMEDIATELY.



WDB

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, Apr 20, 8:15 PM CDT, 3 hours 41 minutes before
ILZ058>060-064-065-069-070-074-079-095>102-MOZ009-010-018-019-026-
027-034>036-041-042-047>052-059>065-072>075-084-085-099-210700-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
815 PM CDT TUE APR 20 1999

THIS OUTLOOK COVERS THE COUNTY WARNING AREA OF THE NWS OFFICE
IN ST. LOUIS. AREAS INCLUDED ARE PARTS OF CENTRAL...NORTHEAST AND
EAST CENTRAL MISSOURI...AND SOUTHWEST ILLINOIS.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER ALL OF THE
COUNTY WARNING AREA TONIGHT.

ALTHOUGH THE WEATHER WAS TRANQUIL ACROSS THE AREA EARLY THIS
EVENING...THE LATEST WEATHER DATA INDICATES THAT THUNDERSTORMS WILL
BE DEVELOPING ACROSS THE REGION AS THE NIGHT PROGRESSES...AND THERE
IS A CHANCE THAT SOME OF THESE STORMS MAY BECOME SEVERE.

SEVERE WEATHER SPOTTERS SHOULD MONITOR LATEST FORECASTS AND OUTLOOKS
AS SKYWARN ACTIVATION MAY BE REQUIRED LATE THIS EVENING...AND DURING
THE PREDAWN HOURS.

TRUETT
Special weather statement, Apr 20, 8:15 PM CDT, 3 hours 41 minutes before
ILZ058>060-064-065-069-070-074-079-095>102-MOZ009-010-018-019-026-
027-034>036-041-042-047>052-059>065-072>075-084-085-099-210700-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
815 PM CDT TUE APR 20 1999

THIS OUTLOOK COVERS THE COUNTY WARNING AREA OF THE NWS OFFICE
IN ST. LOUIS. AREAS INCLUDED ARE PARTS OF CENTRAL...NORTHEAST AND
EAST CENTRAL MISSOURI...AND SOUTHWEST ILLINOIS.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER ALL OF THE
COUNTY WARNING AREA TONIGHT.

ALTHOUGH THE WEATHER WAS TRANQUIL ACROSS THE AREA EARLY THIS
EVENING...THE LATEST WEATHER DATA INDICATES THAT THUNDERSTORMS WILL
BE DEVELOPING ACROSS THE REGION AS THE NIGHT PROGRESSES...AND THERE
IS A CHANCE THAT SOME OF THESE STORMS MAY BECOME SEVERE.

SEVERE WEATHER SPOTTERS SHOULD MONITOR LATEST FORECASTS AND OUTLOOKS
AS SKYWARN ACTIVATION MAY BE REQUIRED LATE THIS EVENING...AND DURING
THE PREDAWN HOURS.

TRUETT

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 21, 12:40 AM CDTSevere Thunderstorm WarningLSXBrown35 min
Apr 20, 9:56 PM CDTSevere Thunderstorm WarningLSXAudrain49 min
Apr 20, 10:45 PM CDTSevere Thunderstorm WarningLSXLewis, Marion35 min
Apr 20, 10:51 PM CDTSevere Thunderstorm WarningLSXAudrain, Monroe49 min
Apr 20, 11:13 PM CDTSevere Thunderstorm WarningLSXPike47 min
Apr 21, 1:36 AM CDTSevere Thunderstorm WarningLSXAudrain49 min
Apr 21, 2:28 AM CDTSevere Thunderstorm WarningLSXAudrain32 min
Apr 21, 2:36 AM CDTSevere Thunderstorm WarningLSXSaint Charles, Warren49 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1999Severe Thunderstorm Warnings in Missouri, 1999Every severe thunderstorm warning in 1999

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.