CSUSM Weather

Weather and Climate at CSUSM

The climate at California State University, San Marcos is characterized by a Mediterranean climate with mild, wet winters and warm, dry summers. The campus experiences:

• 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 60°F (16°C) in summer.
• Rainfall: Most precipitation occurs from November to March, with an annual average of about 15 inches (380 mm).
• Extreme Weather: Rarely, the area can experience Santa Ana winds, which can increase fire risk.

The mild weather at CSUSM facilitates year-round outdoor activities and research, though students and staff should be prepared for occasional heavy rain in winter which can affect commuting.