U.S. equity and options markets are to be closed Monday, and possibly Tuesday, in preparation for Hurricane Sandy.

The various exchanges have announced plans to close trading today as New York state and city officials declare a state of emergency. Initially, the exchanges had planned only to suspend physical trading, but aimed to keep electronic trading going.

Ultimately, however, they agreed to close the markets altogether. The NYSE said Monday that, in consultation with other exchanges and market participants, it will close its markets on Monday, Oct. 29, and pending confirmation on Tuesday, Oct. 30.

“We support the consensus of the markets and the regulatory community that the dangerous conditions developing as a result of Hurricane Sandy will make it extremely difficult to ensure the safety of our people and communities, and safety must be our first priority. We will work with the industry to determine the next steps in restoring trading as soon as the situation permits,” it said.

Earlier, the NYSE had said that it would close the exchange floor, but would keep NYSE Arca open, along with its options markets. The NYSE last suspended physical trading floor operations for a storm on Friday, Sept. 27, 1985 due to Hurricane Gloria.

Nasdaq OMX Group, Inc. is also closing all of its U.S exchanges and markets and the FINRA/Nasdaq Trade Reporting Facility. All of its exchanges outside the U.S. will be open for business as scheduled. Nasdaq also said that its decision was made in consultation with other U.S. exchanges, government officials and regulators, including the US Securities and Exchange Commission (SEC).

“The continuity of our markets and a variety of factors related to Hurricane Sandy’s movement up the Eastern Seaboard were considered, including the state of emergencies declared by New York City, New York State and other state and local governments,” it said.

IntercontinentalExchange, Inc. announced that trading in the ICE Futures Russell equity index futures and options will close early, at 9:15 a.m., and will remain closed for the remainder of the day. Russell settlement prices from Friday will be carried over and used for Monday settlement prices. All other ICE markets and clearing houses will remain open and follow regular market hours.

Additionally, given that U.S. fixed income markets are planning to close at noon today, ICE Clear Credit will close at noon too, it said.

CBOE Holdings, Inc. announced that trading will also be closed for the Chicago Board Options Exchange, CBOE Futures Exchange, C2 Options Exchange, and CBOE Stock Exchange. If additional closures are necessary, it will make a further announcement, it said.