Ontario, California Weather:
Monday, August 17, 2026
Sunny Weather
Day 93°
Night 66°
Precipitation 3 %
Wind 5 mph
UV Index (0 - 11+) 10
Weather Forecast History
Last Year's Weather on This Day (August 17, 2025)
Night

Day

86°

Night

61°

Wind

6 mph

Precipitation

0 %