Alert archive / Illinois / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 258, NWS St. Louis, MO
NWS St. Louis, MO issued this severe thunderstorm warning at Jun 20, 1998, 12:44 AM CDT for Monroe County, Saint Clair County, Illinois. It was in force for 66 min. 4 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
- Jun 20, 1998, 12:44 AM CDT (05:44 UTC)
- Expired
- Jun 20, 1998, 1:50 AM CDT
- In force
- 66 min
- Issued by
- NWS St. Louis, MO
- Area
- Whole counties
Counties Monroe County, IL, Saint Clair County, IL
The radar
The St Louis radar (KLSX), 66 km from the middle of the area, began a volume at 05:47 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jun 20, 12:58 AM CDT | Thunderstorm Wind 55 | Waterloo, IL | |
| Jun 20, 1:05 AM CDT | Thunderstorm Wind 55 | Waterloo, IL | |
| Jun 20, 1:25 AM CDT | Hail 0.75 | Smithton, IL | |
| Jun 20, 1:30 AM CDT | Thunderstorm Wind 55 | Marissa, 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
Lincoln, IL (KILX), launched 00:00Z, 5.7 hours before the alert went out and 234 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2156 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 48 m²/s²
- 0-3 km storm-relative helicity
- 99 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KSTL 200544 RRA SVRSTL ILC133-163-200650- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE ST LOUIS MO 1244 AM CDT SAT JUN 20 1998 THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... MONROE COUNTY ILLINOIS IN SOUTHWESTERN ILLINOIS ST CLAIR COUNTY IN SOUTHWESTERN ILLINOIS * UNTIL 150 AM CDT * AT 1245 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS 10 MILES WEST OF WATERLOO... MOVING EAST AT 40 MPH. * LOCATIONS THAT WILL BE AFFECTED... WATERLOO MAEYSTOWN COLUMBIA NEW ATHENS FREEBURG MILLSTADT SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND GUSTS IN EXCESS OF 60 MPH...DAMAGING HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OR YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD. FG/DM
The office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 20, 1:24 AM CDT | Severe Thunderstorm Warning | LSX | Randolph | 46 min |
| Jun 20, 1:32 AM CDT | Severe Thunderstorm Warning | LSX | Clinton, Washington | 48 min |
| Jun 20, 3:34 AM CDT | Severe Thunderstorm Warning | LSX | Monroe | 51 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.