572  
WWUS73 KLSX 210748  
NPWLSX  
 
URGENT - WEATHER MESSAGE  
NATIONAL WEATHER SERVICE ST LOUIS MO  
248 AM CDT TUE JUL 21 2026  
 
ILZ069-074-079-100>102-MOZ041-047>051-059>065-072>075-084-085-099-  
212300-  
/O.CON.KLSX.HT.Y.0004.000000T0000Z-260722T0000Z/  
CLINTON IL-WASHINGTON IL-RANDOLPH IL-MADISON IL-SAINT CLAIR IL-  
MONROE IL-BOONE MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-  
MONTGOMERY MO-GASCONADE MO-WARREN MO-SAINT CHARLES MO-FRANKLIN MO-  
SAINT LOUIS MO-SAINT LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-  
WASHINGTON MO-SAINT FRANCOIS MO-SAINTE GENEVIEVE MO-IRON MO-  
MADISON MO-REYNOLDS MO-  
INCLUDING THE CITIES OF SPARTA, FARMINGTON, CHESTER, WASHINGTON,  
CAHOKIA, SAINT LOUIS, ALTON, SULLIVAN, BELLEVILLE, FULTON,  
EDWARDSVILLE, COLUMBIA, JEFFERSON CITY, SAINT CHARLES, AND UNION  
248 AM CDT TUE JUL 21 2026  
   
..HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING
 
 
* WHAT...HEAT INDEX VALUES OF 100 TO 110 DEGREES.  
 
* WHERE...PORTIONS OF SOUTH CENTRAL AND SOUTHWEST ILLINOIS AND  
CENTRAL, EAST CENTRAL, AND SOUTHEAST MISSOURI.  
 
* WHEN...UNTIL 7 PM CDT THIS EVENING.  
 
* IMPACTS...HOT TEMPERATURES AND HIGH HUMIDITY MAY CAUSE HEAT  
ILLNESSES.  
 
* ADDITIONAL DETAILS...THIS IS THE FOURTH STRAIGHT DAY WITH HEAT  
INDEX VALUES OF 100 DEGREES OR HIGHER OVER PARTS OF THE AREA.  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
DRINK PLENTY OF FLUIDS, STAY IN AN AIR-CONDITIONED ROOM, STAY OUT OF  
THE SUN, AND CHECK UP ON RELATIVES AND NEIGHBORS. YOUNG CHILDREN AND  
PETS SHOULD NEVER BE LEFT UNATTENDED IN VEHICLES UNDER ANY  
CIRCUMSTANCES. TAKE EXTRA PRECAUTIONS IF YOU WORK OR SPEND TIME  
OUTSIDE. WHEN POSSIBLE RESCHEDULE STRENUOUS ACTIVITIES TO EARLY  
MORNING OR EVENING. KNOW THE SIGNS AND SYMPTOMS OF HEAT EXHAUSTION  
AND HEAT STROKE. WEAR LIGHTWEIGHT AND LOOSE FITTING CLOTHING WHEN  
POSSIBLE. TO REDUCE RISK DURING OUTDOOR WORK, THE OCCUPATIONAL SAFETY  
AND HEALTH ADMINISTRATION RECOMMENDS SCHEDULING FREQUENT REST BREAKS  
IN SHADED OR AIR CONDITIONED ENVIRONMENTS. ANYONE OVERCOME BY HEAT  
SHOULD BE MOVED TO A COOL AND SHADED LOCATION. HEAT STROKE IS AN  
EMERGENCY! CALL 9 1 1.  
 

 
 

 
 
BRITT  
 
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