Across the United States, winter storms are colliding with a warmer atmosphere and a disrupted Arctic, turning familiar ...

The polar vortex is a large-scale weather pattern that typically keeps the coldest air confined to the Arctic region. However, during winter months, this vortex can become unstable, leading to ...

A brutal Arctic outbreak has plunged much of the United States into subzero wind chills, snarling travel and straining power ...