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Hurricanes in California? Not

Californians have a number of natural disasters to worry about, like earthquakes, fires, and mudslides, but one they don’t have to be concerned about is hurricanes.

Hurricanes do form in the Pacific, but they rarely strike land on the United States west coast. On the other hand the hurricanes that form in the Atlantic, the Gulf of Mexico, and the Caribbean hit the U.S. mainland on average about twice a year.

There are two main reasons U.S. west coasters are spared this one impact on their quality of life. The first is that both Atlantic and Pacific hurricanes tend to move with the tradewinds toward the west-northwest. In the Atlantic and Pacific, hurricanes usually form fairly far south of the U.S. mainland. You can see that if the storms move west-northwest they will tend to move toward the mainland in the east, and away from the mainland in the west.

The other major factor is the temperature of the water along the two coasts. Hurricanes form over water, and the water must be warm. During the hurricane season the water temperature along the east coast is at least eighty degrees Fahrenheit. The heat released from the warm moist air that rises from the warm water and condenses is what drives and sustains a hurricane.

By contrast, the water off the U.S. west coast rarely gets above seventy degrees. Hurricanes cannot form over such cool water, and any that form over the warm water farther south cannot maintain their strength when they get to the cool water off the U.S. west coast. Storms from farther south that do strike southern California will have lost their hurricane-force winds by then, although they will still bring heavy rain.

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