California is known for being a state with amazing weather.  When determining which city in the state has the best weather, we really need to look at the southern part of the state. The reason is that the southern cities in California are more recognized for their pleasant year-round temperatures and numerous days of sunshine.

The city with the best weather in California is San Diego. It has the best weather because of its pleasant year-round temperatures, which average out to be around 64°F.  San Diego also has great sunny weather almost all year long with only about 24 days of rain.

Data to confirm San Diego has the best weather has been included below.  To do an accurate comparison of cities, it is important to look at the numbers for the average temperatures, rainfall, and even air quality. 

San Diego Has Best Weather in California?

San Diego has pleasant warm temperatures throughout the year.  Temperatures during the hottest months range from a high of 79°F to a low of 66°F.  During the coldest months, temperatures range from a high of 66°F to a low of 49°F. As you can see, there are not many extreme temperature fluctuations throughout the year; this is no doubt why so many people enjoy going to San Diego at different times of the year to enjoy the nice weather.  

Compared to the rest of California, San Diego’s annual temperature is on average 4.5% higher than the rest of the state.  This is partially due to its southern coastal location, which helps bring in the warm ocean air. 

How Much Does it Rain in San Diego?

San Diego has around 266 days of sunshine a year, and it only rains about 24 days of the year.  When compared to the rest of the state it rains about 45% less in San Diego. 

Since there is not much rain in San Diego, you would think that the humidity would be relatively low, but it will often be more humid in San Diego in the morning due to its coastal location.  Then with the rising temperatures throughout the day, it will become less humid in the afternoons.  For example, on average, there is about 74% humidity in the morning, and then by the afternoon it is around 62%.  

Throughout the year, the average humidity in San Diego is around 81%, which is in line with the average throughout the rest of the state.  Typically, you will find the summer months to have the highest humidity and the winter months will have the lowest humidity. 

Ocean Temperature in San Diego

The water in the Pacific Ocean can be cold across California. But since San Diego is closer to the equator, the water can be a more pleasant temperature than other places in California. 

On average, the water temperatures range from a low of 57°F during the winter months to a high of 68°F.  So, if you want to go surfing or swimming in the ocean, it is probably best to do that during the summer months. 

Does San Diego Have a Lot of Pollution?

Another topic associated with weather and is important to note when talking about the city with the best climate in California is pollution. 

Air quality ratings are based on the Air Quality Index (AQI), which is used by the government across the United States.  The index has ranged from “Good” air quality to “Hazardous.”  In general, San Diego usually stays within the “Moderate” range during the year.

During the summer months this can change due to wildfires which are becoming more frequent and dangerous across San Diego and the state. 

Natural Events in San Diego

California is on a fault line and does have earthquakes throughout the state.  However, earthquakes happening in San Diego are less likely when compared with the rest of the state.  When you look at the Earthquake Index, which is calculated based on historic earthquake events, San Diego ranks number 912 out of 1814 places in California.


Without a doubt, San Diego has the best weather in California, based on the average annual temperatures and the number of sunny days versus rainy days.  The weather in San Diego is enjoyable year-round, with summers that are not too hot and winters that are not too cold.  You might even be able to go and enjoy the beach in the winter months, too, although you may need to be a little brave to get into the water at that time of year. 

However, during the summer months, you can enjoy the water almost every day.  If the beach is not for you, then don’t worry there are plenty of outdoor events and activities to do in the city of San Diego.