Ontario, California Weather:
Thursday, September 17, 2026
Sunny Weather
Day 84°
Night 61°
Precipitation 1 %
Wind 6 mph
UV Index (0 - 11+) 7
Weather Forecast History
Last Year's Weather on This Day (September 17, 2025)
Rainy Weather

Day

93°

Night

68°

Wind

6 mph

Precipitation

90 %