Originally Posted by Peregrine415
AFAIK the difference is all international flights arrive/depart from PVG.
SHA handles domestic flights within China.
That is essentially correct, but there are also a number of domestic flights from/to PVG. Definitely no scheduled international flights at SHA anymore though, though SHA is sometimes used when PVG is closed due to weather problems.
The airports are far enough apart (mainly because PVG is so far from the city) for the weather to be totally different sometimes.