Alert archive / Illinois / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 37, NWS St. Louis, MO
NWS St. Louis, MO issued this severe thunderstorm warning at Feb 27, 1999, 11:34 AM CST for Madison 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
- Feb 27, 1999, 11:34 AM CST (17:34 UTC)
- Expired
- Feb 27, 1999, 12:40 PM CST
- In force
- 66 min
- Issued by
- NWS St. Louis, MO
- Area
- Whole counties
Counties Madison County, IL, Saint Clair County, IL
The radar
The St Louis radar (KLSX), 67 km from the middle of the area, began a volume at 17:38 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 |
|---|---|---|---|
| Feb 27, 11:52 AM CST | Hail 1 | O Fallon, IL | |
| Feb 27, 12:05 PM CST | Tornado F0 | Troy, IL | |
| Feb 27, 12:15 PM CST | Hail 1.75 | Edwardsville, IL | |
| Feb 27, 12:45 PM CST | Hail 1 | Highland, 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 12:00Z, 5.6 hours before the alert went out and 202 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
- 107 J/kg
- Mixed-layer CIN
- -160 J/kg
- Mixed-layer LCL
- 635 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 275 m²/s²
- 0-3 km storm-relative helicity
- 325 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
999 WUUS1 KSTL 271736 RRA SVRSTL ILC119-163-271840- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE ST LOUIS MO 1134 AM CST SAT FEB 27 1999 THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... MADISON COUNTY ILLINOIS IN SOUTHWESTERN ILLINOIS NORTHERN ST CLAIR COUNTY IN SOUTHWESTERN ILLINOIS * UNTIL 1240 PM CST * AT 1133 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM ST LOUIS CITY... MOVING NORTHEAST AT 35 MPH. * LOCATIONS THAT WILL BE AFFECTED... GRANT CITY EDWARDSVILLE COLLINSVILLE EAST ST LOUIS CENTREVILE GOLF BALL SIZED HAIL AT ST LOUIS CITY THE PRIMARY SEVERE WEATHER THREAT IS DAMAGING HAIL. LARGE HAIL CAN CAUSE EXTENSIVE PROPERTY DAMAGE AN SERIOUS INJURY TO PEOPLE CAUGHT OUTDOORS. MOVE INSIDE A STURDY BUILDING IMMEDIATELY. TES/RP &
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, Feb 27, 7:56 AM CST, 3 hours 38 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>075-084-085-099-261700- SEVERE WEATHER OUTLOOK NATIONAL WEATHER SERVICE ST LOUIS MO 750 AM CST FRIDAY FEB 26 1999 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 THE SOUTHEASTERN PORTION OF THE COUNTY WARNING AREA THIS AFTERNOON AND EVENING. THE AREA AFFECTED IS GENERALLY SOUTH AND EAST OF A CHESTERFIELD MISSOURI TO VICHY MISSOURI LINE. THE THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE LARGE HAIL. SKYWARN PERSONNEL AND EMERGENCY MANAGEMENT OFFICIALS SHOULD STAY ABREAST OF LATEST FORECASTS AND OUTLOOKS SHOULD SKYWARN ACTIVATION BECOME NECESSARY LATER TODAY. WDB
The office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 27, 11:51 AM CST | Tornado Warning | LSX | Madison, Saint Clair | 49 min |
| Feb 27, 12:11 PM CST | Severe Thunderstorm Warning | LSX | Monroe | 34 min |
| Feb 27, 12:13 PM CST | Tornado Warning | LSX | Monroe | 47 min |
| Feb 27, 12:26 PM CST | Tornado Warning | LSX | Bond, Clinton | 44 min |
| Feb 27, 12:45 PM CST | Severe Thunderstorm Warning | LSX | Fayette | 50 min |
| Feb 27, 12:49 PM CST | Severe Thunderstorm Warning | LSX | Saint Clair | 46 min |
| Feb 27, 1:05 PM CST | Severe Thunderstorm Warning | LSX | Monroe | 50 min |
| Feb 27, 1:07 PM CST | Severe Thunderstorm Warning | LSX | Clinton | 48 min |
| Feb 27, 1:26 PM CST | Severe Thunderstorm Warning | LSX | Randolph | 49 min |
| Feb 27, 1:37 PM CST | Severe Thunderstorm Warning | LSX | Marion | 48 min |
Nearby
Severe Thunderstorm Warnings in Illinois, 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; radar from the NEXRAD Level II archive.