Forecasters have compared Hurricane Sandy with the "perfect storm," or the Halloween Nor'easter, which hit the same weekend in 1991.
In 1991, Hurricane Grace merged with a cold front. The resulting storm killed 13 people and caused $200 million in damage.
Even though Hollywood immortalized the perfect storm, it never made landfall.
Sandy is forecast to merge with a powerful front in the Great Lakes.
The big difference is Sandy is expected to make landfall, which could mean damage would be worse.
It is also expected to have lower pressure, which would mean more power for the storm.