Unusual winter storm warnings hit three states, but what's the cause?

A winter storm warning was issued with up to 32 inches of snow and dangerous 60 mph winds is coming this week.

A winter storm warning was issued by the National Weather Service as two feet of heavy snow is coming this weekend.

Heavy mountain snow is now giving way to powerful winds across the Northern Rockies, with up to 16 inches forecast in Montana ...

A 'Winter Storm Warning' in the final days of June is set to bring heavy snow of up to three feet and winds gusting to 60mph ...

Freezing temperatures and travel impacts are expected into Thursday morning in parts of Idaho, Nevada and three other states.

Photo: Lars Penning/dpa (Photo by Lars Penning/picture alliance via Getty Images) Heavy snow returns, causing low visibility and travel warnings in the region. National Weather Service warns of ...

A rare late-June snowstorm could bury the mountain roads to Yellowstone, Grand Teton, and Glacier under up to 8 inches of wet ...