I read a study today on each of the times the NY Stock Exchange has closed on what would have been a normal business day. The average result the day it next opened? – nearly unchanged. There were only two days on which it moved more than 1%. The first was after the JFK funeral when it went up 3%. The other was after 9/11 when it dropped 4%.
The near-term trend on the market right now is down and with earnings season being disappointing and people selling energy and insurance stocks because of Hurricane Sandy, I expect the market will open lower, but not by any more than a normal day.
When the market will open again depends on what the flood damage is and whether people can get to the exchange, particularly the IT guys that keep everything working. I have not yet heard a definite decision on whether the NYSE will open on Wednesday but we should hear later today.