Rancho Cucamonga, California Weather:
Monday, May 18, 2026
Sunny Weather
Day 81°
Night 55°
Precipitation 0 %
Wind 7 mph
Weather Forecast History
Last Year's Weather on This Day (May 18, 2025)
Cloudy Weather

Day

73°

Night

52°

Wind

8 mph

UV Index

8

Precipitation

4 %