Rancho Cucamonga, California Weather:
Sunday, May 17, 2026
Cloudy Weather
Day 81°
Night 57°
Precipitation 80 %
Wind 7 mph
Weather Forecast History
Last Year's Weather on This Day (May 17, 2025)
Rainy Weather

Day

64°

Night

55°

Wind

11 mph

UV Index

3

Precipitation

55 %