When to Go
The best time to visit Shanghai is early spring or early fall, when the weather is good and crowds diminish. Although temperatures are scorching and the humidity can be unbearable, summer is the peak tourist season, and hotels and transportation can get very crowded.
Avoid the two main public holidays, Chinese New Year (which ranges from mid-January to mid-February) and the National Day holiday (always the first week of October), when a billion-plus people are on the move.