When is the first day of fall in California?

Fall does not have a specific start date in California as the state does not experience distinct seasons in the same way as other parts of the world. California has a Mediterranean climate, characterized by mild, wet winters and warm, dry summers.

The National Weather Service does not define specific start and end dates for seasons based on temperature changes or weather patterns in California. Instead, seasons are generally defined based on astronomical events.

In the Northern Hemisphere, including California, the astronomical start of fall is the autumn equinox, which usually occurs around September 22 or 23 each year. This marks the day when the length of day and night are nearly equal, and the Earth's axis is tilted neither toward nor away from the sun.

However, it's important to note that the transition from summer to fall in California is gradual and can vary from region to region. Some areas may start to experience cooler temperatures and changes in foliage earlier or later than others, depending on factors such as elevation, proximity to the coast, and local weather patterns.