The first thing you need to know is that under normal circumstances, travelling on a 1 070-foot ship means that you barely even feel the ocean.

Norwegian Escape, of the Norwegian Cruise fleet, is one such ship. It left the Cape Liberty Cruise Port across the Hudson from New York City about 3PM on Sunday, bound for Port Canaveral in Florida.

Before it could reach its destination, however, freak weather intervened. The Washington Post with the details:

Shortly before midnight, the ship suddenly lurched to port. An onboard video shows passengers — who moments earlier had been celebrating the first night of their cruise — duck and cover as tables, chairs and cutlery became projectiles. The ship was northeast of the Delmarva Peninsula when it happened.

Check it out:

Here’s more footage:

You have to appreciate the calmness of the videographer.

Injuries were reported, and people were treated by the medical staff onboard. The ship was undamaged.

The culprit for the commotion? What Norwegian described as a “sudden, extreme gust of wind, estimated at 100 knots.” That’s 115 mph — above the threshold for a Category 3 hurricane.

“It strikes me as a freak thing,” said Jonathan O’Brien, a meteorologist at the National Weather Service office in Mount Holly, N.J. “We’ve seen the video, and it happened not too far off our coastline. But it wasn’t a hugely powerful system.”

The freak gust of wind has left meteorologists puzzled, but a barometer trace from a buoy off Cape May, New Jersey, shows that the centre of low pressure had been passing overhead at that point.

Doppler radar reveals a number of heavy downpours — and a few thunderstorms — in the storm system’s “comma head” region nearby at the time.

Despite air temperatures in the upper 30s to near 40, a powerful thunderstorm developed on the leading edge of a wind-shift line. Some of the precipitation on the northern end of the squall was falling as snow. The storm quickly became a “bow echo,” a backward C-shaped storm where strong winds cause the line of storms to bow out in the middle.

Even still, it’s unlikely that winds more than 60 mph to 70 mph would have accompanied that storm. And they would have lasted about 10 minutes. This gust of wind was one-and-done.

The other possibility is that it was a shallow waterspout.

Radar shows a bit of rotation along the wind-shift line. Since the thunderstorm cell is so far away from the radar dome, we can’t see closer to the ground. There might have been a funnel hanging down below that the beam overshot.

Most waterspouts have winds of 50 mph to 60 mph. If it was attached to the thunderstorm above — which was moving northeast at 60 mph — that could account for a brief, sporadic gust to 115 mph. There would be no way to see it coming, and no buildup.

Yep, that sounds about right.

Whatever caused it, I’m sure the passengers on board were just happy to make it out alive.

[source:washingtonpost]