458  
WGUS63 KLOT 181847  
FFALOT  
 
URGENT - IMMEDIATE BROADCAST REQUESTED  
FLOOD WATCH  
NATIONAL WEATHER SERVICE CHICAGO IL  
147 PM CDT FRI SEP 18 2026  
 
ILZ003>005-008-190415-  
/O.NEW.KLOT.FA.A.0016.260919T0600Z-260919T1800Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
WINNEBAGO-BOONE-MCHENRY-OGLE-  
INCLUDING THE CITIES OF WOODSTOCK, BYRON, BELVIDERE, ROCHELLE,  
ROCKFORD, MCHENRY, ALGONQUIN, OREGON, AND CRYSTAL LAKE  
147 PM CDT FRI SEP 18 2026  
 
...FLOOD WATCH IN EFFECT FROM 1 AM CDT SATURDAY THROUGH SATURDAY  
MORNING...  
 
* WHAT...FLASH FLOODING CAUSED BY EXCESSIVE RAINFALL IS POSSIBLE.  
 
* WHERE...PORTIONS OF NORTH CENTRAL AND NORTHEAST ILLINOIS, INCLUDING  
THE FOLLOWING COUNTIES, IN NORTH CENTRAL ILLINOIS, BOONE, OGLE AND  
WINNEBAGO. IN NORTHEAST ILLINOIS, MCHENRY.  
 
* WHEN...FROM 1 AM CDT SATURDAY THROUGH SATURDAY MORNING.  
 
* IMPACTS...CREEKS AND STREAMS MAY RISE OUT OF THEIR BANKS. ROADS AND  
STREETS MAY BE FLOODED.  
 
* ADDITIONAL DETAILS...  
- SHOWERS AND THUNDERSTORMS OVERNIGHT INTO SATURDAY MORNING MAY  
PRODUCE WIDESPREAD RAINFALL RATES UP TO 2 INCHES PER HOUR THAT  
COULD LEAD TO FLASH FLOODING.  
 
ADDITIONAL THUNDERSTORMS SATURDAY EVENING INTO EARLY SUNDAY  
MORNING HAVE THE POTENTIAL TO PRODUCE TORRENTIAL RAINFALL THAT  
RESULTS IN FLASH FLOODING, THOUGH THE EXACT PLACEMENT OF THIS  
RAINFALL REMAINS UNCLEAR. A SECOND FLOOD WATCH FOR FLASH FLOODING  
MAY BE NEEDED DURING THIS PERIOD.  
- HTTP://WWW.WEATHER.GOV/SAFETY/FLOOD  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
A FLOOD WATCH FOR FLASH FLOODING MEANS RAPID-ONSET FLOODING IS  
POSSIBLE, BUT NOT YET CERTAIN, BASED UPON THE LATEST FORECASTS. FLASH  
FLOODING IS A DANGEROUS SITUATION. PERSONS WITH INTERESTS ALONG AREA  
RIVERS, CREEKS, AND OTHER WATERWAYS SHOULD MONITOR THE LATEST  
FORECASTS AND BE PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP.  
 

 
 

 
 
ILZ006-010>013-020-103>106-INZ001-002-190415-  
/O.NEW.KLOT.FA.A.0016.260919T0900Z-260919T1800Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
LAKE IL-LEE-DE KALB-KANE-DUPAGE-KENDALL-NORTHERN COOK-CENTRAL  
COOK-SOUTHERN COOK-NORTHERN WILL-LAKE IN-PORTER-  
INCLUDING THE CITIES OF PLANO, EVANSTON, AURORA, WAUKEGAN, CALUMET  
CITY, MOKENA, NAPERVILLE, CHICAGO, YORKVILLE, MERRILLVILLE, DEKALB,  
LEMONT, ELGIN, ORLAND PARK, HAMMOND, NORTHBROOK, MUNDELEIN,  
SCHAUMBURG, DES PLAINES, JOLIET, GURNEE, PARK FOREST, PLAINFIELD,  
CAROL STREAM, OSWEGO, PALATINE, CICERO, VALPARAISO, DOWNERS GROVE,  
OAK PARK, CHESTERTON, SYCAMORE, LOMBARD, PORTAGE, GARY, OAK LAWN,  
BOLINGBROOK, BUFFALO GROVE, WHEATON, LA GRANGE, OAK FOREST, AND DIXON  
147 PM CDT FRI SEP 18 2026  
 
...FLOOD WATCH IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY  
MORNING...  
 
* WHAT...FLASH FLOODING CAUSED BY EXCESSIVE RAINFALL IS POSSIBLE.  
 
* WHERE...PORTIONS OF ILLINOIS, INCLUDING THE FOLLOWING AREAS, COOK,  
DE KALB, DUPAGE, KANE, KENDALL, LAKE, LEE, AND NORTHERN WILL AND  
NORTHWEST INDIANA, INCLUDING THE FOLLOWING AREAS, LAKE AND PORTER.  
 
* WHEN...FROM LATE TONIGHT THROUGH SATURDAY MORNING.  
 
* IMPACTS...CREEKS AND STREAMS MAY RISE OUT OF THEIR BANKS. FLOODING  
MAY OCCUR IN POOR DRAINAGE AND URBAN AREAS. ROADS AND STREETS MAY  
BE FLOODED.  
 
* ADDITIONAL DETAILS...  
- SHOWERS AND THUNDERSTORMS LATE TONIGHT THROUGH SATURDAY MORNING  
MAY PRODUCE WIDESPREAD RAINFALL RATES UP TO 2 INCHES PER HOUR  
THAT COULD LEAD TO FLASH FLOODING, PARTICULARLY OVER URBAN AREAS.  
 
ADDITIONAL THUNDERSTORMS SATURDAY EVENING INTO EARLY SUNDAY  
MORNING HAVE THE POTENTIAL TO PRODUCE TORRENTIAL RAINFALL THAT  
RESULTS IN FLASH FLOODING, THOUGH THE EXACT PLACEMENT OF THIS  
RAINFALL REMAINS UNCLEAR. A SECOND FLOOD WATCH FOR FLASH FLOODING  
MAY BE NEEDED DURING THIS PERIOD.  
- HTTP://WWW.WEATHER.GOV/SAFETY/FLOOD  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
A FLOOD WATCH FOR FLASH FLOODING MEANS RAPID-ONSET FLOODING IS  
POSSIBLE, BUT NOT YET CERTAIN, BASED UPON THE LATEST FORECASTS. FLASH  
FLOODING IS A DANGEROUS SITUATION. PERSONS WITH INTERESTS ALONG AREA  
RIVERS, CREEKS, AND OTHER WATERWAYS SHOULD MONITOR THE LATEST  
FORECASTS AND BE PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP.  
 

 
 

 
 
KLUBER  
 
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