Severe blizzards on the east coast of the US have led to the cancellation of a number of flights to and from Europe.
Airports in New York, Boston, Chicago, Philadelphia and Washington are affected with fierce blizzards and strong winds which are expected to get worse.
A number of flights to Ireland have been delayed and one Aer Lingus flight from New York to Dublin has been cancelled.
Boston's Logan airport said it was forced to close as crews could not keep runways clear. Bradley International Airport in Connecticut was also shuttered until midday today, a state emergency management official said.
Massachusetts Governor Mitt Romney declared a state of emergency on Saturday, allowing him to call on the National Guard if needed.
Officials said New Englanders were generally heeding warnings to stay off roads amid the risk of deep snow drifts. In Connecticut and Massachusetts, about 3,000 customers were without power as of 9 a.m., emergency officials said.
Washington-area airports were open today, with some flight delays due to closures or severely curtailed flights out of airports in the Northeast.
The Washington region received 4 inches to 7 inches (10 to 18 cm) of snow on Saturday.
The US Midwest was digging out from the storm that snarled travel when it dumped more than a foot of snow in some areas starting on Friday night.
High winds and poor visibility produced white-out conditions and times, making driving treacherous. More than 440 flights had been canceled at Chicago's two main airports, the city's aviation department said on Saturday.
A further 372 flights were canceled at the airports on Friday, and flights that were able to take off were subject to delays of up to a few hours.