The weather pattern that’s dominated the United States for most of January jumped into overdrive this week. Nearly all of the 48 contiguous states are unusually cold, though it’s a pale imitation of the colossal, nationwide Arctic intrusions of decades past. In our warming climate, such 20th-century cold outbreaks may become increasingly tougher to match. Yet winter can still pack a dangerous punch, as folks on the Gulf Coast and in California are finding in two very different ways. Historic, city-snarling snowfall – in some cases, possibly the heaviest in more than a century – was spreading on Tuesday into coastal communities from Texas toward Florida. … Meanwhile, high winds, bone-dry air, and tinder-dry vegetation continue to plague coastal Southern California, just weeks after the area was hit by one of the most catastrophic fire events in modern U.S. history.