Whiteout cause is a term used to describe the conditions that can lead to a whiteout. A whiteout is a weather phenomenon where visibility is reduced due to SNOW or blowing SNOW. The two crossword solutions for this term are SNOW (4 letters) and SNOWSQUALL (10 letters). SNOW is a type of precipitation in the form of flakes of crystalline water ice that falls from clouds. A snowsquall is a sudden, brief, intense snowstorm with strong winds and poor visibility.