I went to Berkeley, California in the summer vacation. What was the weather like then?

I'm studying in Berkeley, and I have to take classes in the summer ~ Actually, because Berkeley is close to the sea, the weather is generally a little cooler than that in cities further away, but because the campus roads are difficult to walk (all slopes are like climbing mountains). . . ), it may be hot. But no matter how cool it is, it is still summer. The sun in California is quite poisonous. If you are afraid of the sun, you can try to wear a thin coat to keep out the sun. The weather in northern California is not boring even if it is hot, and I often wear long-sleeved shirts in summer. Basically, short sleeves, shorts, trousers and thin coats can be brought, and shoes should be comfortable to walk with, otherwise walking on campus will hurt. The weather in California is very different from day to night. Even if you go out in the evening or in the morning on a hot day, it will be a little cold and you need a coat. The air conditioning in the school library is sometimes quite fierce, so it is better to bring a coat.