Last year it was an earthquake and Hurricane Irene that caused extensive damage up and down the east coast. This week officials are bracing for Hurricane Sandy.
Dr. Louis Uccellini, director of NOAA's National Centers for Environmental Prediction, says Sandy could hit the region hard.
"I want to emphasize here that the lateral extent of the heavy rainfall has danger for river flooding in Pennsylvania and Maryland and into northern Virginia," he says.
But Dr. Uccellini also says it's hard to tell how extensive the flooding could be.
"Right now we don't have the wet ground that we had before Irene, so there's a bit more uncertainty into the magnitude of the flooding, but given the amount of rainfall and the period of time that it's falling over, we expect the river flooding to be significant," he says.
Besides flooding, officials are also bracing for high-speed winds, which could cause extensive power outages across the region.