If we travel to Beijing, Hangzhou,Suzhou and Shanghai what would the weather be like in early June

As for Beijing, it can be a little cool in the morning and night, and hot at noon. The temp may range from 16C to 28C during the day and night. Cloudy days will be in the majority and it may rain a little.

For the other three, the weather is similar. It may be hot and wet (thundershower). According to the weather records, the average temp can be 25C. Prepare a long sleeved shirt and several summer clothing.