Simulations as early as March 16 indicated a wave of low pressure would rapidly intensify sometime around the weekend of the 23rd and 24th between Iceland and Norway. But it wasn't clear at the time exactly where.
It's not unusual to have intense cyclones develop in this part of the world in March.
The equinoctial seasons are known for their vicious transitions, often manifest by violent open-ocean storms. The northeast Atlantic is a notoriously rough patch of maritime real estate in the late winter and early spring, often spinning up gales that can threaten even the most experienced captains.
The forecast became much clearer last Thursday into Friday NZT, when it appeared obvious that the central coast of Norway would be hard-hit.
The Viking Sky departed Bergen, Norway, on March 14, bound for a port-hopping excursion northward up the coast. It would then turn around and hit several cities on its way south, eventually steaming to Tilbury, England.
But the storm was on a crash-course with the Viking Sky's desired path. The ship could have remained docked on Bodø to ride out the storm. Instead, it continued south, becoming stranded and prompting an airlift evacuation. The Viking Sky arrived safely into the port of Molde on Monday.
Helicopters fly over the cruise ship Viking Sky after it sent out a Mayday signal because of engine failure in windy conditions.
A significant wave height of 13.2m was reported on Sunday at the Heidrun buoy by weather.us. This reflects just an average of the biggest waves and several may have been taller, even topping 18m.
Waves are a byproduct of wind, and they take time to build to such impressive heights. Nine metre waves occurred for an astonishing 17 consecutive hours at the same station.
The winds were extreme, measuring 140km/h over the open ocean and clocking in closer to 112km/h nearest to shore. At Svinøy fyr - 95km southwest of where Viking Star is currently docked - winds hit 110km/h.
In ordinary circumstances, the Viking Sky can cruise at 20 knots, or 37 km/h. That would have been enough time for it to make it back to shore within a half-hour or so, since most of its journey was spent in sight of land.
The issue in this case was the engine failure, which could not have been planned for.
Passengers on board the Viking Sky, waiting to be evacuated.
So while the ship did continue to operate in treacherous weather, it likely was not a conscious decision - unlike Royal Caribbean's Anthem of the Seas' infamous 2018 encounter with a "bomb cyclone".
The lack of ability to navigate or turn the ship also left the Viking Sky susceptible to being broadsided by waves.
Several large breakers ploughed into the ship, smashing windows and shattering glass.
Video shows the ship listing to and fro at nearly 20 degrees to the horizontal. That's because the ship's 29m width tucked it in between wave crests, exposing the vessel to maximum sideways rocking motion when a wave passed through.
The storm system has since dissipated, weakening over the Norwegian and Barents Seas.
The incident is set to be probed by the Norwegian Accident Investigations Board.
