California Institute of Technology Weather

Weather and Climate at Caltech

The California Institute of Technology, located in Pasadena, experiences a Mediterranean climate characterized by warm, dry summers and mild, wet winters.

• Temperature: Average highs range from 65°F (18°C) in winter to 85°F (29°C) in summer, with lows around 45°F (7°C) in winter and 65°F (18°C) in summer.
• Rainfall: Most precipitation occurs from November to March, averaging about 20 inches (508 mm) annually.
• Extreme Weather: While rare, the area can experience heatwaves and occasional Santa Ana winds, which can increase fire risk.
• Impact on Campus Life: The mild climate generally supports year-round outdoor activities and research, though heavy rain can affect commuting and outdoor experiments during winter months.