627  
WGUS63 KLSX 181856  
FFALSX  
 
URGENT - IMMEDIATE BROADCAST REQUESTED  
FLOOD WATCH  
NATIONAL WEATHER SERVICE ST LOUIS MO  
156 PM CDT MON MAY 18 2026  
 
ILZ098-099-MOZ034>036-042-191000-  
/O.EXB.KLSX.FA.A.0004.000000T0000Z-260519T1800Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
CALHOUN IL-JERSEY IL-MONROE MO-RALLS MO-PIKE MO-AUDRAIN MO-  
INCLUDING THE CITIES OF MEXICO AND BOWLING GREEN  
156 PM CDT MON MAY 18 2026  
   
..FLOOD WATCH IN EFFECT THROUGH TUESDAY AFTERNOON  
 
* WHAT...FLASH FLOODING CAUSED BY EXCESSIVE RAINFALL CONTINUES TO BE  
POSSIBLE.  
 
* WHERE...PORTIONS OF SOUTHWEST ILLINOIS, INCLUDING THE FOLLOWING  
AREAS, CALHOUN IL AND JERSEY IL AND MISSOURI, INCLUDING THE  
FOLLOWING AREAS, AUDRAIN MO, MONROE MO, PIKE MO AND RALLS MO.  
 
* WHEN...THROUGH TUESDAY AFTERNOON.  
 
* IMPACTS...EXCESSIVE RUNOFF MAY RESULT IN FLOODING OF RIVERS,  
CREEKS, STREAMS, AND OTHER LOW-LYING AND FLOOD-PRONE LOCATIONS.  
 
* ADDITIONAL DETAILS...  
- POTENTIAL RAINFALL AMOUNTS OF 2 TO 4 INCHES, WITH LOCALIZED  
HIGHER AMOUNTS OF 4 TO 6 INCHES.  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION  
SHOULD FLASH FLOOD WARNINGS BE ISSUED.  
 
 
 
 
 
ILZ064-065-069-070-074-MOZ041-047>051-059-060-062-072-073-191000-  
/O.EXT.KLSX.FA.A.0004.000000T0000Z-260519T1800Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
BOND IL-FAYETTE IL-CLINTON IL-MARION IL-WASHINGTON IL-BOONE MO-  
MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-GASCONADE  
MO-WARREN MO-FRANKLIN MO-CRAWFORD MO-WASHINGTON MO-  
INCLUDING THE CITIES OF FULTON, VANDALIA, UNION, COLUMBIA, JEFFERSON  
CITY, SALEM, CENTRALIA, SULLIVAN, AND WASHINGTON  
156 PM CDT MON MAY 18 2026  
   
..FLOOD WATCH NOW IN EFFECT THROUGH TUESDAY AFTERNOON  
 
* WHAT...FLASH FLOODING CAUSED BY EXCESSIVE RAINFALL CONTINUES TO BE  
POSSIBLE.  
 
* WHERE...PORTIONS OF SOUTH CENTRAL ILLINOIS, INCLUDING THE FOLLOWING  
AREAS, BOND IL, CLINTON IL, FAYETTE IL, MARION IL AND WASHINGTON IL  
AND MISSOURI, INCLUDING THE FOLLOWING AREAS, BOONE MO, CALLAWAY MO,  
COLE MO, CRAWFORD MO, FRANKLIN MO, GASCONADE MO, MONITEAU MO,  
MONTGOMERY MO, OSAGE MO, WARREN MO AND WASHINGTON MO.  
 
* WHEN...THROUGH TUESDAY AFTERNOON.  
 
* IMPACTS...EXCESSIVE RUNOFF MAY RESULT IN FLOODING OF RIVERS,  
CREEKS, STREAMS, AND OTHER LOW-LYING AND FLOOD-PRONE LOCATIONS.  
 
* ADDITIONAL DETAILS...  
- POTENTIAL RAINFALL AMOUNTS OF 2 TO 4 INCHES, WITH LOCALIZED  
HIGHER AMOUNTS OF 4 TO 6 INCHES.  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION  
SHOULD FLASH FLOOD WARNINGS BE ISSUED.  
 
 
 
 
 
ILZ100>102-MOZ052-061-063>065-191000-  
/O.EXT.KLSX.FA.A.0004.000000T0000Z-260519T1800Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
MADISON IL-SAINT CLAIR IL-MONROE IL-LINCOLN MO-SAINT CHARLES MO-  
SAINT LOUIS MO-SAINT LOUIS CITY MO-JEFFERSON MO-  
INCLUDING THE CITIES OF EDWARDSVILLE, SAINT LOUIS, BELLEVILLE, ALTON,  
SAINT CHARLES, AND CAHOKIA  
156 PM CDT MON MAY 18 2026  
   
..FLOOD WATCH NOW IN EFFECT THROUGH TUESDAY AFTERNOON  
 
* WHAT...FLASH FLOODING CAUSED BY EXCESSIVE RAINFALL CONTINUES TO BE  
POSSIBLE.  
 
* WHERE...PORTIONS OF SOUTHWEST ILLINOIS, INCLUDING THE FOLLOWING  
AREAS, MADISON IL, MONROE IL AND SAINT CLAIR IL AND EAST CENTRAL  
MISSOURI, INCLUDING THE FOLLOWING AREAS, JEFFERSON MO, LINCOLN MO,  
SAINT CHARLES MO, SAINT LOUIS CITY MO AND SAINT LOUIS MO.  
 
* WHEN...THROUGH TUESDAY AFTERNOON.  
 
* IMPACTS...EXCESSIVE RUNOFF MAY RESULT IN FLOODING OF RIVERS,  
CREEKS, STREAMS, AND OTHER LOW-LYING AND FLOOD-PRONE LOCATIONS.  
 
* ADDITIONAL DETAILS...  
- POTENTIAL RAINFALL AMOUNTS OF 2 TO 4 INCHES, WITH LOCALIZED  
HIGHER AMOUNTS OF 4 TO 6 INCHES.  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
YOU SHOULD MONITOR LATER FORECASTS AND BE ALERT FOR POSSIBLE FLOOD  
WARNINGS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE PREPARED  
TO TAKE ACTION SHOULD FLOODING DEVELOP.  
 
 
 
 
 
BAH  
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