Whiteout (weather)

Reduced visibility due to snow or sand

Whiteout or white-out is a weather condition in which visibility and contrast are severely reduced by snow, fog, or sand. The horizon disappears from view while the sky and landscape appear featureless, leaving no points of visual reference by which to navigate. A whiteout may be due simply to extremely heavy snowfall rates as seen in lake effect conditions, or to other factors such as diffuse lighting from overcast clouds, mist or fog, or a background of snow.

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