Most of the hurricanes that affect the United States form in the Atlantic Ocean off the coast of Africa and travel west towards America. A smaller number come together in the Caribbean or Gulf of Mexico and move north.
In the Pacific Ocean, many hurricanes form off the western Mexican coast and travel westward through the ocean. Others form off the coast of Japan, or in the southern Pacific Ocean near Australia. Hurricanes can also appear in the Indian Ocean, where they may move in any direction.
Hurricanes and cyclones that form in the Northern Hemisphere tend to bend northward, while those in the Southern Hemisphere trend southward. This is due to the Coriolis effect, the movement the Earth's spin imposes on their circulation patterns.