WASHINGTON (AP) -- Much of the East Coast has a good chance of getting hit by gale-force winds, flooding, heavy rain and maybe even snow early next week by an unusual hybrid of hurricane and winter storm.

Though still projecting several days ahead of Halloween week, the computer models are spooking meteorologists. Government scientists say the storm has a 70 percent chance of smacking the Northeast and mid-Atlantic.

Hurricane Sandy in the Caribbean, an early winter storm in the West, and a blast of arctic air from the North are predicted to collide, sloshing and parking over the country's most populous coastal corridor starting Sunday. The worst of it should peak early Tuesday, but it will stretch into midweek.

Forecaster Jim Cisco of the National Oceanic and Atmospheric Administration says "We don't have many modern precedents for what the models are suggesting."

It is likely to hit during a full moon when tides are near their highest, increasing coastal flooding potential. Some meteorologists fear that with some trees still leafy and the potential for snow, power outages could last to Election Day. They say it has all the earmarks of a billion-dollar storm.

Some have compared it to the so-called Perfect Storm that struck off the coast of New England in 1991, but Cisco says that one didn't hit as populated an area and is not comparable to what the East Coast may be facing.