UPDATE 4-U.S. Northeast digs out after storm snarls travel
* Major airports reopen but long backlog for flights
* Airlines may need days to work through snow disruptions
* BA plane spends 8 hours on airport tarmac after landing
* Boston, Philadelphia, other cities also dig out (Adds airline details, mayor's quote)
NEW YORK, Dec 28 (Reuters) - New York dug out of its sixth biggest snowstorm on record and thousands of stranded travelers hoped to finally board long-delayed flights on Tuesday after a blizzard buried the northeastern United States the day after Christmas.
The city's normally busy streets were largely empty, many still unplowed, and commuter rail service struggled to resume regular operations after the storm dumped 20 inches (50.8 cm) over a 17-hour period on Sunday and Monday.
Financial markets operated normally.
"At first it was somewhat exciting and pretty cool to see this much snow, being from Texas, but by the second day it became pretty frustrating. The sidewalks were a mess," said tourist Will Robinson, 24.
Boston, Philadelphia and other cities on the Atlantic Coast also got pummeled with similar snowfall and crept back to life after an extended holiday hiatus when garbage went uncollected, offices stayed shut and shoppers stayed home on what normally is one of the busiest retail days of the year.
With 4,500 flights canceled or delayed on Sunday and Monday in New York's three major airports, tens of thousands of passengers camped out in terminals. Airlines could need days to work through the backlog, officials said.
A British Airways BAY.L jet was left for nearly eight hours on the tarmac at John F. Kennedy International Airport after landing on a flight from London on Tuesday. The airline blamed gate congestion and a lack of immigration and customs personnel.
Delays at JFK were running about five hours, said Ed Martelle, a spokesman for AMR Corp AMR.N, the parent of American Airlines. Operations at Boston's Logan International Airport were almost back to normal.
"This is kind of the perfect storm for airlines. We've dealt with big snows before, but this was a really big storm stretched over a really big area," Martelle said. "I won't say it's unprecedented, but we haven't seen this for a while."
In Philadelphia, 305 stranded passengers spent Monday night at the airport, down from 1,215 on Sunday night, an airport spokeswoman said.
In Boston, tens of thousands of customers were left without power after 18.2 inches (46 cm) of snow fell, 10th most since the National Weather Service started keeping records in 1892. The state of Massachusetts lifted its state of emergency and public transit operated with only minor hitches.
NEW YORK RESPONSE CRITICIZED
The 20 inches (50.8 cm) of snow that fell on Central Park marked the sixth largest New York City snowfall since records have been kept, a weather service spokeswoman said. Up to 32 inches (81 cm) fell in New Jersey. Winds reached 65 mph (105 kph).
The New York record of 26.4 inches (67.1 cm) was set on Feb. 11-12, 2006.
True to character, New Yorkers complained about storm relief while the city's fleet of 2,000 snow-plowing sanitation trucks struggled to clear the city's 6,000 miles (9,600 km) of streets.
After ambulances and city buses got stuck and many neighborhoods outside Manhattan had yet to see plows, accusations rained in that City Hall failed to prepare for a blizzard that was forecast days in advance.
"If your street was plowed, the response was adequate. If your street was not plowed, it wasn't adequate. Yelling and complaining about it doesn't help," Mayor Michael Bloomberg told a news conference.
Times Square was mostly cleared in preparation for Friday night's New Year's Eve celebration. Warmer and mostly sunny weather was forecast until then.
Traffic trickled over a thin layer of slush, after the so-called crossroads of the world had almost no cars on Monday when snow was piled high. (Additional reporting by Bernd Debusmann Jr. and Edith Honan in New York, Ros Krasny in Boston, Jon Hurdle in Philadelphia and Kyle Peterson in Chicago; editing by Mohammad Zargham)