Hurricane Sandy will probably grow into a “Frankenstorm” that may become the worst to hit the U.S. Northeast in 100 years if current forecasts are correct. Sandy may combine with a second storm coming out of the Midwest to create a system that would rival the New England hurricane of 1938 in intensity, said Paul Kocin, a National Weather Service meteorologist in College Park, Maryland. The hurricane currently passing the Bahamas has killed 21 people across the Caribbean, the Associated Press reported, citing local officials.