Remnants of Sandy moved over Pennsylvania on Wednesday, the National Weather Service announced. Flood warnings are also in effect in the Great Lakes region, and heavy snow has been falling in the Appalachian Mountains.

"Now we are looking at flooding on Lake Erie, possibly Lake Michigan," Homeland Security Secretary Janet Napolitano said. "We're looking at secondary flooding downstream as rivers fill with the remnants of Sandy and the water has to go somewhere. We are now in recovery mode - response and recovery - we are moving large amounts of resources into the affected areas. "

Six million customers across the Northeast still lack electricity.

Spots of normal

New York Mayor Michael Bloomberg reopened the New York Stock Exchange on Wednesday morning. Buses resumed transport of commuters, but it could take an extra day for subways and commuter trains to reopen.

New York's JFK airport, as well as neighboring Newark airport, began limited service after thousands of canceled flights. New York's LaGuardia Airport was flooded and remained closed.

Sunday's New York Marathon will go on as scheduled, but Wednesday night's Halloween parade through Greenwich Village has been postponed. On Broadway, shows that had been canceled since Sunday were due to mostly resume on Wednesday, the Theater League announced.

Long recovery

Half of the service stations in the New York City area and New Jersey were shut on Wednesday due to power outages and depleted fuel supplies. It could take weeks to recover from power and mass transit outages thus far.

With a week to go before the US presidential election, President Barack Obama will visit New Jersey, where Sandy made landfall Monday as the largest storm to hit the United States in generations. Obama will be accompanied by Republican Governor Chris Christie, a vocal backer of presidential challenger Mitt Romney. Nevertheless, Christie has praised Obama and the federal response to the storm.

Sandy killed 27 in New York State, including 22 in New York City, and six each in New Jersey and Pennsylvania. Nine states reported a total of over 60 fatalities.

mkg/mz (AFP, Reuters, dpa, AP)