Alert archive / Illinois / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 110, NWS St. Louis, MO

May 20, 1998Adams County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at May 20, 1998, 8:52 AM CDT for Adams County, Illinois. It was in force for 33 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
May 20, 1998, 8:52 AM CDT (13:52 UTC)
Expired
May 20, 1998, 9:25 AM CDT
In force
33 min
Issued by
NWS St. Louis, MO
Area
Whole counties

County Adams County, IL

The radar

The St Louis radar (KLSX), 150 km from the middle of the area, began a volume at 13:56 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
May 20, 9:10 AM CDTThunderstorm Wind 51(Uin)Quincy Muni Arp, IL

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 nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 1.9 hours before the alert went out and 190 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, Davenport, at 12:00Z on 1998-05-20Temperature 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, Davenport, at 12:00Z on 1998-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 50 square meters per square second.193958Sfc1 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
2431 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
50 m²/s²
0-3 km storm-relative helicity
176 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSTL 201351 RRA
SVRSTL
ILC001-201425-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
852 AM CDT WED MAY 20 1998

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN ADAMS COUNTY IN WEST CENTRAL ILLINOIS

* UNTIL 925 AM CDT

* AT 849 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM JUST NORTH OF QUINCY REGIONAL AIRPORT...
  MOVING EAST SOUTHEAST AT 20 MPH.

* LOCATIONS THAT WILL BE AFFECTED...
  QUINCY AIRPORT
  KINGSTON

GOLFBALL SIZE HAIL WAS REPORTED EAST OF QUINCY

THIS STORM HAS A HISTORY OF DAMAGING HAIL. STAY INSIDE AND AWAY
FROM WINDOWS.



GKS/DF


&
:

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, 6:00 AM CDT, 2 hours 52 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>075-084-085-099-201700-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
600 AM CDT WED MAY 20 1998

THIS OUTLOOK COVERS THE COUNTY WARNING AREA OF THE NATIONAL WEATHER
SERVICE FORECAST OFFICE IN ST LOUIS.  AREAS INCLUDED ARE PORTIONS OF
NORTHEAST...CENTRAL...EAST CENTRAL AND SOUTHEAST MISSOURI AS WELL AS
WEST CENTRAL AND SOUTHWEST ILLINOIS.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER CENTRAL...
EAST CENTRAL AND NORTHEAST MISSOURI AND ADJACENT SECTIONS OF WEST
CENTRAL ILLINOIS.

A LINE OF STRONG THUNDERSTORMS OVER NORTHWEST MISSOURI IS EXPECTED
TO CONTINUE EAST THIS MORNING BRINGING A THREAT OF SEVERE THUNDER-
STORMS TO NORTHEAST MISSOURI AND WEST CENTRAL ILLINOIS BY MID-MORNING.
FURTHER SOUTH THE RISK OF SEVERE WEATHER WILL BE MAINLY DURING THE
AFTERNOON AND EVENING HOURS.  A WEAK COLD FRONT ACROSS NORTHERN
MISSOURI IS FORECAST TO DROP SOUTH TO NEAR THE MISSOURI
RIVER BY THIS EVENING.  THIS FRONT WILL HELP SET OFF THUNDERSTORMS
ACROSS CENTRAL AND EAST CENTRAL MISSOURI.

STORM SPOTTER GROUPS AND EMERGENCY MANAGERS SHOULD MONITOR
ADDITIONAL WEATHER DEVELOPMENTS FOR POSSIBLE SKYWARN ACTIVATION.

FERRY
Special weather statement, May 20, 6:00 AM CDT, 2 hours 52 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>075-084-085-099-201700-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
600 AM CDT WED MAY 20 1998

THIS OUTLOOK COVERS THE COUNTY WARNING AREA OF THE NATIONAL WEATHER
SERVICE FORECAST OFFICE IN ST LOUIS.  AREAS INCLUDED ARE PORTIONS OF
NORTHEAST...CENTRAL...EAST CENTRAL AND SOUTHEAST MISSOURI AS WELL AS
WEST CENTRAL AND SOUTHWEST ILLINOIS.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER CENTRAL...
EAST CENTRAL AND NORTHEAST MISSOURI AND ADJACENT SECTIONS OF WEST
CENTRAL ILLINOIS.

A LINE OF STRONG THUNDERSTORMS OVER NORTHWEST MISSOURI IS EXPECTED
TO CONTINUE EAST THIS MORNING BRINGING A THREAT OF SEVERE THUNDER-
STORMS TO NORTHEAST MISSOURI AND WEST CENTRAL ILLINOIS BY MID-MORNING.
FURTHER SOUTH THE RISK OF SEVERE WEATHER WILL BE MAINLY DURING THE
AFTERNOON AND EVENING HOURS.  A WEAK COLD FRONT ACROSS NORTHERN
MISSOURI IS FORECAST TO DROP SOUTH TO NEAR THE MISSOURI
RIVER BY THIS EVENING.  THIS FRONT WILL HELP SET OFF THUNDERSTORMS
ACROSS CENTRAL AND EAST CENTRAL MISSOURI.

STORM SPOTTER GROUPS AND EMERGENCY MANAGERS SHOULD MONITOR
ADDITIONAL WEATHER DEVELOPMENTS FOR POSSIBLE SKYWARN ACTIVATION.

FERRY

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 9:18 AM CDTSevere Thunderstorm WarningLSXBrown47 min
May 20, 9:21 AM CDTSevere Thunderstorm WarningLSXMacoupin64 min
May 20, 9:24 AM CDTSevere Thunderstorm WarningLSXBrown41 min

Nearby

Severe Thunderstorm Warnings in Illinois, 1998Every severe thunderstorm warning in 1998

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; radar from the NEXRAD Level II archive.