Alert archive / Illinois / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 39, NWS St. Louis, MO
NWS St. Louis, MO issued this severe thunderstorm warning at May 17, 1991, 5:42 PM CDT for Randolph County, Illinois; Sainte Genevieve County, Missouri. It was in force for 63 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 17, 1991, 5:42 PM CDT (22:42 UTC)
- Expired
- May 17, 1991, 6:45 PM CDT
- In force
- 63 min
- Issued by
- NWS St. Louis, MO
- Area
- Whole counties
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 17, 6:15 PM CDT | Thunderstorm Wind 0 | Randolph, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Paducah/Barkley, KY (KPAH), launched 12:00Z, 10.7 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.
- Mixed-layer CAPE
- 1509 J/kg
- Mixed-layer CIN
- -34 J/kg
- Mixed-layer LCL
- 669 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- -61 m²/s²
- 0-3 km storm-relative helicity
- -40 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -1.1
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KSTL 172243 RRA SVRSTL ILC157-MOC186-172345- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE ST LOUIS MO 542 PM CDT FRI MAY 17 1991 THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 645 PM CDT FOR PEOPLE IN THE FOLLOWING LOCATIONS... IN SOUTHWEST ILLINOIS ...RANDOLPH COUNTY IN EAST CENTRAL MISSOURI ...STE GENEVIEVE COUNTY AT 525 PM...THE ST. GENEVIEVE COUNTY SHERIFF REPORTED MARBLE SIZE HAIL IN ST GENEVIEVE AND TREES WERE BLOWN OVER IN THE NORTHERN PART OF THE COUNTY. RADAR INDICATED TWO STORMS IN ST GENEVIEVE COUNTY...ONE IN THE WESTERN PART OF THE COUNTY THE OTHER WAS IN EASTERN ST. GENEVIEVE COUNTY... THIS IS ABOUT 50 MILES SOUTHE OF ST LOUIS. THE STORMS WERE MOVING EAST NORTHEAST AT 25 MILES AN HOUR. PEOPLE IN THE TOWNS OF ST. GENEVIEVE AND SPARTA ILLINOIS SHOULD MOVE TO A PLACE OF SAFETY. WHEN THUNDERSTORMS ARE OCCURRING...PEOPLE SHOULD MOVE INSIDE A STRONG BUILDING. DO NOT STAND BY WINDOWS. DON'T USE TELEPHONES OR ELECTRICAL APPLIANCES UNLESS IN AN EMERGENCY UNTIL THE STORM HAS PASSED. MOTORISTS SHOULD NOT DRIVE INTO LOW WATER CROSSINGS. FERRY
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 17, 12:00 PM CDT, 5 hours 42 minutes before
MOZALL-171910- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ST LOUIS MO 1201 PM CDT FRI MAY 17 1991 ...SEVERE THUNDERSTORMS AND HEAVY RAIN POSSIBLE IN THE ST. LOUIS AREA LATE THIS AFTERNOON AND TONIGHT... CONDITIONS ARE RIPE FOR THE POSSIBILITY OF SEVERE THUNDERSTORM DEVELOPMENT OVER CENTRAL MISSOURI LATE THIS AFTERNOON AND TONIGHT. IN ADDITION...SOME STORMS MAY PRODUCE LOCALLY HEAVY RAIN DUE TO THE VERY MOIST AIR OVER THE AREA. IF YOU LIVE NEAR LOW LYING AREAS...CREEKS...OR STREAMS IN THE ST. LOUIS METRO AREA...STAY ALERT TONIGHT. IF HEAVY RAINS MOVE INTO YOUR AREA...FLOODING OF LOW LYING AREAS...CREEKS...AND UNDERPASSES MAY OCCUR. DO NOT DRIVE THROUGH FLOODING ROADS. STAY TUNED TO LOCAL TV BROADCASTS OR NOAA WEATHER RADIO FOR THE LATEST STATEMENTS ON THIS WEATHER SITUATION. GOETSCH
Special weather statement, May 17, 3:57 PM CDT, 1 hour 45 minutes before
MOZ001>003-005>007-172200- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ST LOUIS MO 355 PM CDT FRI MAY 17 1991 ...A TORNADO WATCH IS IN EFFECT FOR NORTH CENTRAL AND NORTHEAST MISSOURI TILL 9 PM... AT 345 PM...THUNDERSTERSTORMS WERE OCCURRING OVER NORTH CENTRAL MISSOURI. THE STRONGEST STORM WAS NORTHEAST OF TRENTON. THE STORM WAS MOVING NORTHEAST AT 25 MILES AN HOUR. THUNDERSTORMS WILL CONTINUE TO DEVELOP OVER THIS PART OF MISSOURI LATE THIS AFTERNOON AND THIS EVENING. SOME OF THESE STORMS WILL REACH SEVERE LIMITS AND MAY ALSO PRODUCE TORNADOES. IF YOU ARE IN NORTHEAST AND NORTH CENTRAL MISSOURI...OR ARE PLANNING TO TRAVEL INTO THIS AREA...MONITOR THE WEATHER CONDITIONS CLOSELY BY LISTENING TO NOAA WEATHER RADIO AND LOCAL RADIO AND T.V. STATIONS. BE PREPARED TO TAKE IMMEDIATE ACTION IN THE EVENT THAT SEVERE WEATHER DEVELOPES. FERRY
Special weather statement, May 17, 5:09 PM CDT, 33 minutes before
MOZ012-018-172300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ST LOUIS MO 500 PM CDT FRI MAY 17 1991 ...THUNDERSTORMS WERE DEVELOPING OVER SOUTHEAST MISSOURI... AT 500 PM...A STRONG THUNDERSTORM WAS LOCATED JUST EAST OF MONTAUK STATE PARK IN SOUTHWEST DENT COUNTY. THIS IS ABOUT 50 MILES SOUTH OF ROLLA. SOME PEA SIZE HAIL WAS REPORTED FROM THIS STORM AT MONTAUK STATE PARK JUST BEFORE 5 PM. IN ADDITION TO THE HAIL...EXTREMELY HEAVY RAINS WILL ALSO OCCUR WITH THIS STORM. THIS STORM WAS MOVING NORTHEAST AT 20 MILES AN HOUR AND WILL BE MOVING THROUGH OR NEAR THE TOWNS OF GLADDEN AND SALEM BY 6 PM. PERSONS IN THIS AREA SHOULD MONITOR THE WEATHER CLOSELY AND BE PREPARED TO MOVEt TO SAFETY IN THE EVENT THIS STORM INTENSIFIES. FERRY
The office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 17, 3:58 PM CDT | Severe Thunderstorm Warning | LSX | Schuyler | 47 min |
| May 17, 4:46 PM CDT | Severe Thunderstorm Warning | LSX | Schuyler, Scotland | 59 min |
| May 17, 5:49 PM CDT | Severe Thunderstorm Warning | LSX | Clark, Scotland | 56 min |
| May 17, 6:39 PM CDT | Severe Thunderstorm Warning | LSX | Lewis | 51 min |
Nearby
Severe Thunderstorm Warnings in Illinois, 1991Severe Thunderstorm Warnings in Missouri, 1991Every severe thunderstorm warning in 1991
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.