Questions on Shanghai world expo.

I am living on the equator where it is always either sunny or rainy but I am going to Shanghai World Expo 4 days later I want to ask what weather it is there to know what kind of clothes to bring.I also want to know tips about Shanghai world expo on which pavilion to visit since I heard it takes a long time to finish queuing for 1 pavilion.If you have went there,please give some advices!~