The US climate is characterized by wide variations, not just from region to region and season to season but also day to day and hour to hour. Even setting aside far-flung Alaska and Hawaii, the continental US is subject to dramatically shifting weather patterns, most notably produced by westerly winds sweeping across the continent from the Pacific. As a general rule, however, temperatures tend to rise the further south you go, and to fall the higher you climb, while the climate along either coast is, on the whole, milder and less volatile than inland. What follows is a rough outline of the country’s weather patterns from the eastern seaboard to the west.
The Northeast, from Maine down to Washington DC, experiences low precipitation as a rule, but temperatures can range from bitterly cold in winter to uncomfortably hot and humid in the summer. Further south, summers get warmer and longer. Florida’s air temperatures are not dramatically high in summer, being kept down by the proximity of the sea both east and west, but humidity is also a problem; in the winter, the state is warm and sunny enough to attract many visitors.
The central expanse of the Great Plains, which for climatic purposes can be said to extend from the Appalachians to the Rockies, are alternately exposed to seasonal icy Arctic winds streaming down from Canada and humid tropical airflows from the Caribbean and the Gulf of Mexico. Winters around the Great Lakes and Chicago can be abjectly cold, with driving winds and freezing rain. It can freeze or even snow in winter as far south as the Gulf of Mexico, though spring and autumn get progressively longer and milder further south through the Plains. Average rainfall dwindles to lower and lower levels the further west you head across the Plains. In the Midwest tornadoes (or “twisters”) are a frequent local phenomenon, tending to cut a narrow swath of destruction in the wake of violent spring or summer thunderstorms.
In the South as a whole summer is much the wettest season, with high humidity, and the time when thunderstorms are most likely to strike. One or two hurricanes each year rage across Florida and/or the Gulf of Mexico states from the warm waters to the south between August and October. The winter is mild for the most part and the two shoulder seasons usually see warm days and fresher nights
Temperatures in the Rockies correlate closely with altitude, so nights can be cold even in high summer. Beyond the mountains in the south lie the extensive arid and inhospitable deserts of the Southwest. Much of this area is within the rain shadow of the California ranges. In cities such as Las Vegas and Phoenix, the mercury regularly soars above 100°F, though the atmosphere is not usually humid enough to be as enervating as that might sound and air conditioning is ubiquitous.
West of the barrier of the Cascade Mountains, the fertile Pacific Northwest is the only region of the country where winter is the wettest season, and outside summer the climate is wet, mild and seldom hot. Further south, California’s weather more or less lives up to the popular idyllic image, though the climate is markedly hotter and drier in the south than in the north, where there’s enough snow to make the mountains a major skiing destination from November to April. San Francisco and the northern coast is kept milder and colder than the inland region by its propensity to attract sea fog, while much of the Los Angeles basin is prone to filling up with smog – though this diminishes the closer you get to the ocean.
All US cities are pretty much year-round destinations, with some exceptions (Fairbanks, Alaska, in winter and Houston, Texas, in summer, for example, can be quite unpleasant), while national parks and mountain ranges tend to be seasonal attractions; this is particularly true of the summer months between Memorial and Labor days, when the majority of domestic tourists visit.Read More