605  
CDUS46 KSGX 220024  
CLIONT  
 
CLIMATE REPORT  
NATIONAL WEATHER SERVICE SAN DIEGO, CA  
524 PM PDT THU AUG 21 2025  
   
...............................
 
 
   
..THE ONTARIO INTL AIRPORT CA CLIMATE SUMMARY FOR AUGUST 21 2025
 
 
VALID TODAY AS OF 0400 PM LOCAL TIME.  
 
CLIMATE NORMAL PERIOD: 1991 TO 2020  
CLIMATE RECORD PERIOD: 1998 TO 2025  
 
WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST  
VALUE (LST) VALUE VALUE FROM YEAR  
NORMAL    
...............................................................
 
 
TEMPERATURE (F)  
TODAY  
MAXIMUM 103R 2:38 PM 103 2020 95 8 99  
MINIMUM 74 5:49 AM 57 2011 65 9 69  
AVERAGE 89 80 9 84  
 
PRECIPITATION (IN)  
TODAY 0.00 0.23 2023 0.00 0.00 0.00  
MONTH TO DATE 0.00 0.02 -0.02 T  
SINCE JUL 1 0.00 0.07 -0.07 T  
SINCE OCT 1 6.22 11.53 -5.31 17.64  
SINCE JAN 1 6.07 8.43 -2.36 16.29  
 
DEGREE DAYS  
HEATING  
TODAY 0 0 0 0  
MONTH TO DATE 0 0 0 0  
SINCE JUN 1 0 4 -4 2  
SINCE JUL 1 0 0 0 0  
 
COOLING  
TODAY 24 15 9 19  
MONTH TO DATE 312 315 -3 393  
SINCE JUN 1 945 1007 -62 1198  
SINCE JAN 1 1195 1221 -26 1259    
...............................................................
 
 
WIND (MPH)  
RESULTANT WIND SPEED 4 RESULTANT WIND DIRECTION SW (240)  
HIGHEST WIND SPEED 18 HIGHEST WIND DIRECTION W (270)  
HIGHEST GUST SPEED 25 HIGHEST GUST DIRECTION SW (240)  
AVERAGE WIND SPEED 4.3  
 
SKY COVER  
POSSIBLE SUNSHINE MM  
AVERAGE SKY COVER 0.5  
 
WEATHER CONDITIONS  
THE FOLLOWING WEATHER WAS RECORDED TODAY.  
HAZE  
 
RELATIVE HUMIDITY (PERCENT)  
HIGHEST 48 7:00 AM  
LOWEST 19 12:00 PM  
AVERAGE 34  
   
......................................................
 
 
THE ONTARIO INTL AIRPORT CA CLIMATE NORMALS FOR TOMORROW  
NORMAL RECORD YEAR  
MAXIMUM TEMPERATURE (F) 95 104 1998  
MINIMUM TEMPERATURE (F) 65 59 2002  
 
SUNRISE AND SUNSET  
AUGUST 21 2025........SUNRISE 6:17 AM PDT SUNSET 7:30 PM PDT  
AUGUST 22 2025........SUNRISE 6:17 AM PDT SUNSET 7:29 PM PDT  
 
- INDICATES NEGATIVE NUMBERS.  
R INDICATES RECORD WAS SET OR TIED.  
MM INDICATES DATA IS MISSING.  
T INDICATES TRACE AMOUNT.  
 

 
 
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