1. San Francisco is cloudy all year round. It's cold in the morning and hot at noon. You'd better take a coat and trousers. July is around 16 and 17 degrees.

Compared with San Francisco, Los Angeles is warmer, about 20 degrees. It's sunny in Los Angeles, so it's recommended to take a thin coat that can shade the sun. It's strange to play with a parasol in America. )

It's about 20 degrees in new york in July, because it's cooler near the sea!

Boston is close to new york, and the temperature is similar, but it is colder than new york and similar to San Francisco.

5. Washington, you may be talking about Washington DC. The temperature in July is around 25 degrees!

Generally speaking, you'd better bring a pair of trousers, a long-sleeved shirt and a thin long-sleeved shirt. Short sleeves, shorts and skirts are ok! If you are traveling, it is recommended to wear comfortable clothes, such as a piece of clothing, as little as possible, just one or two! There are many casual clothes in America, and formal dresses are worn at parties and small parties. Take one or two in case you go to a fancy restaurant or casino!

I hope I can help you!

Have a nice trip!