I live in Savannah which is about 30 minutes south of HIlton Head. The weather varies quite a bit in March. Usually it starts to warm up before St. Patrick's Day, but we always get a cold spell at some point in the month. We are having it now. It got down to 30 degrees last night. But it will be 60 by this afternoon. Last week we hit 80. Once the weather warms up, the gnats come out. But if you are by the beach, the wind keeps them away. Hope this helps some.