It is getting warm in late March, not too many rain as it is in early March. The temperature is usually around 15C. You can buy Shanghai snacks, confectionery and preserved fruit. To east, you can get to Yuyuan Garden. There is a snack town in that area. It is expensive, but undounbted a good place to see and try Shanghai snacks in the fatest way. For Qipao and Fabric, you can visit the fabric market in Nanpu Bridge. There are tailors there. However, I am not farmilar with the price.