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Eastern Pacific Hurricane Season

May 15 marks the statistical peak of the eastern Pacific hurricane season. There’s a much less pronounced peak in the eastern Pacific season than in the Atlantic hurricane season, but its storms tend to be likeliest (by a small margin) on or about August 29. By November 30, the eastern Pacific hurricane season ends.

Eastern Pacific storms aren't talked about as much in the continental U.S. because they usually don’t do much damage there. Atlantic hurricanes travel west and slam into the Americas; Pacific hurricanes form off Mexico and head northwest into wide open ocean. They sometimes double back to hit the mainland, but Pacific Ocean temperatures are much cooler than the warm Gulf Stream waters that help drive Atlantic storms, sapping the storms of their strength as they travel. One notable exception is the hurricane that hit San Diego in 1858 - but that just shows how rare they are.

If an eastern Pacific hurricane should manage to travel far enough west that it crosses the International Dateline before breaking up, it’s rechristened as a typhoon, which are what hurricanes are called in Asia. It doesn’t happen often, but it happened in early August 2014, when Hurricane Genevieve morphed into Typhoon Genevieve without missing a beat.