What causes snow storms to develop?

The distance required for this to occur is at least tens of miles, and usually 100 miles or more. A third class of snowstorm is "orographic", which occurs in mountainous regions, where air is forced to rise as it flows over the mountains causing large snowfall accumulations. read more

Snow storms are usually caused by rising moist air within an extratropical cyclone (low pressure area. The cyclone forces a relatively warm, moist air mass up and over a cold air mass. If the air near the surface is not sufficiently cold over a deep enough layer, the snow will fall as rain instead. read more

Winter storms develop when low pressure systems come into contact with a cold front or a warm front, which causes low temperature precipitation such as snow and freezing rain. Common types of winter storms caused by low pressure systems include snow storms, ice storms and blizzards. read more