Passengers of the cruise Safari Endeavour take a polar plunge at Frederick Sound. Stephen's Passage. Petersberg. Alaska. USA. The Polar Plunge was offered here in Gut Bay this morning, at 9:45am and 11:00am. But with mild temperatures and relatively warm water (for Alaska), most who participated in the plunge said the water was actually quite refreshing. I nearly did the plunge myself – but stood on deck with a cup of coffee and watched instead.