Hurricanes are actually tropical phenomena that are caused by the evaporation of a large pool of very warm ocean water that happens not too far from a shoreline. The nearest pool of warm water is a very long way from Washington, Oregon or even California. Hurricanes can however strike the Pacific coast typically between about Acapulco and Panama (Central America) and are in fact very common there.

There are two other reasons why we don't get hurricanes in California: Prevailing winds tend to blow toward the west-northwest. In the Atlantic, this direction often brings storms toward the United States. In the Eastern Pacific, a west-northwest track takes hurricanes away from the California coast. Another very important reason is that the water temperature is too cold to sustain tropical storms. The Gulf Stream along the Atlantic provides warm deep water with temperatures above 27 C while the water currents off southern California are only 22 C. The letter "C" here means Centigrades.