Q&A on the News

Q: Do hurricanes happen on the Pacific Coast of the United States and Mexico? — Doris Waddle, Fayetteville A: They are formed in the Northeast Pacific basin, but “almost never” hit the U.S., Christopher W. Landsea with the National Oceanic and Atmospheric Administration’s National Hurricane Center in Miami, told Scientific American. Hurricanes above the equator often move north or northwest, so when they form in the Atlantic, that sometimes puts them on a path to hit the United States.

He said differences in water temperatures is another factor, with Pacific Ocean temperatures often in the low 70s or cooler. According to the NOAA website, one key to the formation of a hurricane is water that is at least 80 degrees.

“Such relatively cool temperatures do not provide enough thermal energy to sustain a hurricane’s strength,” Landsea, branch chief of the center’s Tropical Analysis and Forecast Branch, told Scientific American. “So the occasional Northeast Pacific hurricane that does track back toward the U.S. encounters the cooler waters of the Pacific, which can quickly reduce the storm’s strength.”

Kerry Emanuel, a meteorologist and climate scientist at Massachusetts Institute of Technology, told the magazine, “Occasionally, tropical storms do strike coastal southern California. By the time they do, they have lost their hurricane-force winds, although they may still bring with them very heavy rainfall that can cause extensive flooding.”