It is most common and severe along the higher terrain bordering the Gulf of Alaska, over the Alaskan Peninsula and in southeast Alaska. The relatively warm water of the North Pacific is a readily available source of moisture and the mountains provide a lifting mechanism necessary to produce preci- pitation and icing. Icing should always be considered a threat when flying in clouds or above the freezing level in visible moisture. Mechanical turbulence, generated by strong low-level winds blowing across rugged terrain, occurs frequently in Alaska although mostly during the winter months. During the warmer months, turbulence is usually limited to that associated with scattered thunderstorms, particularly in the interior of Alaska.
Much myth exists on whiteouts.
The most popular is that a whiteout exists during a blizzard condition. This is totally incorrect. Strictly speaking, the whiteout is an optical effect rather than a meteorological phenomenon and it cannot be forecast. Whiteouts can and do occur in any area of Alaska and numerous aircraft accidents have been attributed to them. The necessary conditions for occurrence of a whiteout are snow or ice covered terrain and a cloud layer of uniform thickness covering most of the sky.