BC Ferries is being much more cautious about weather conditions before sailing the Northern Adventure across Hecate Strait in the wake of last month's incident, which saw the ferry trapped and battered for several hours by hurricane-force winds.Ferries cancelled Sunday night's sailing from Prince Rupert to Skidegate (Dec. 20) after Environment Canada predicted waves of three to four metres in Hecate Strait. Spokesperson Deborah Marshall said the Northern Adventure should not sail if waves are higher than 3.6 metres, and the crew took the extra precaution of contacting the weather office directly to confirm the forecast."We looked at the weather forecast and erred on the side of caution," she said. "Safety was the concern."In fact, the waves in Hecate Strait did not get any higher than three metres on Sunday night.Ms Marshall said BC Ferries was aware that the Sunday ferry was full of freight, mail, groceries and islanders coming home for the holiday season, but that there was room for all passengers and vehicles on the Monday night sailing.A few days earlier, BC Ferries made an unusual schedule change due to warnings of a massive storm that hit the islands on Thursday (Dec. 17). Ms Marshall said the crew decided to sail to Skidegate on Wednesday in advance of the storm, a day earlier than scheduled. The ferry waited out the weather in Skidegate, then sailed back to Rupert on Friday morning, a bit later than the scheduled departure of late Thursday night.Only 20 of the 46 passengers who had booked a spot on Thursday's sailing from Prince Rupert to Skidegate made it onto the Northern Adventure for its early departure, Ms Marshall said.But if the ferry hadn't left in advance of the storm, it might not have come to the islands at all, she said. By Friday morning, when the weather cleared, the ferry would still be sitting in Rupert and would be almost 19 hours behind schedule, and it's likely that BC Ferries would have decided to cancel the trip to the islands and left for Port Hardy that afternoon, keeping on schedule."We adjusted our schedule to make the best of a possibly very bad situation," she said. "We know many customers are travelling to visit family and friends for the holidays and we wanted to have the least possible disruption to their plans."The Northern Adventure was carrying 163 passengers, 50 vehicles, four drop trailers, three commercial vehicles and three oversized vehicles when it left Skidegate on Friday, she said.