The NYSE says it will invoke its contingency plans beginning Monday. The New York Mercantile Exchange also will be shutting its trading floor which is located in a mandatory evacuation zone.
Trading has rarely stopped for weather. The NYSE shut down on March 27, 1985 for Hurricane Gloria.
Hurricane Sandy was headed north from the Caribbean, on course to meet a snowstorm and a cold front. Experts said the rare hybrid storm could cause havoc over 800 miles stretching from the East Coast to the Great Lakes.