The United States of America has some diverse weather patterns. Thomas A. Horne‘s book Flying America’s Weather gives you a view of different weather regions around the U.S. from a pilots view. Here is an excerpt from the book discussing weather in the region of California:
For pilots or any other student of meteorology, the state of California represents one of the most interesting weather regions in the United States. It is a state with an abundance of different climatological areas in close proximity to each other, a condition made possible by a unique combination of widely disparate geographic features. This is especially true of southern California, where the pacific Ocean, coastal lowlands, mountain ranges, valleys, and a desert adjoin each other in a strip of land hardly more than 100 miles wide.
As might be expected of a state with 1,340 miles of coastline, California owes a great deal of its weather to the Pacific Ocean, and the air circulating above it. This oceanic circulation has some seasonal aspects central to the nature of California’s summers and winters–especially in southern California. Like the Atlantic Ocean, the Pacific is the site of a large, semipermanent high pressure system. And just as the Atlantic’s Bermuda high affects so much of the eastern United States’ weather, so the Pacific high influences the western coastal areas.
But the differences are great. The clockwise circulation around the “back side” of the Bermuda high sends warm, moist air from the Caribbean and Gulf of Mexico inland. In California, it’s the high’s “front side” that’s at work. Here, the clockwise flow sends air of more moderate temperature from the central pacific to Californian shores.
In the summer months, the Pacific high is situated more or less due west of central California, There, it exercises a blocking function, preventing low pressure areas from traveling to the southern regions of the state. The flow of air is nearly always from the west, both at the surface and aloft, and wind speeds are moderate–seldom exceeding 40 knots even at altitudes as high as 10,000 feet. In the fall and winter, the Pacific high drops to the south, and this permits low pressure and/or cold fronts to strike California as they are pushed through by the northernmost segment of the high’s flows.
In his book,Thomas A. Horne breaks the U.S. into 17 geographical weather regions and discusses weather aspects unique to that particular region. Want to know whats happening in your neck of the woods? Check out theFlying America’s Weather!