By Jamie Yuccas CBS News August 17, 2018, 6:40 PM Rising ocean water temperatures increase risk of Pacific hurricanes

SAN DIEGO — California had it's hottest July ever. But the heat waves weren't only on land.

The Pacific Ocean off San Diego hit a record high this month. Last week, two hurricanes barreled through the Pacific, and there are new concerns that rising seawater temperatures could bring them closer to California.

Irma, Harvey and Katrina are among the hurricanes that have ravaged the East Coast and the Gulf of Mexico. But in California, hurricanes are virtually unheard of.

"I can't imagine that type of devastation hitting the shores here," said Jerry Cook, one San Diego resident.

Hurricanes that form in the eastern Pacific Ocean usually don't make it past Baja, California. Only one managed to reach as far as San Diego in 1858. However, there's now the potential this rare event could strike the San Diego area again.

"It could happen, especially if the ocean temperatures continue to stay in this anomalous warm state," said Art Miller, an oceanographer.

Scientists at the Scripps Pier have been recording historic temperatures in the Pacific Ocean as high as 79.5 degrees. That's about 10 degrees above normal.

"It shows that we have been right at or outside of the record temps that were already set back in the 30s. So we know we are experiencing a very extreme temperature event," said Clarissa Anderson, executive director of the Southern California Coastal Ocean Observing System.

"That potentially increases the likelihood that a hurricane might track just a little bit further north than it would have," Miller said.

Even though California has been battle-tested by fires, mudslides and earthquakes, the widespread impact of a hurricane on lives and property is still unknown.

"The risks associated with those high wind events might be surprising. … We haven't tested for that type of natural phenomena in our current system," Miller said.

The National Weather Service has found temperatures even higher in parts of the Pacific. One reason is that the ocean absorbs more heat than land and normal winds in Southern California haven't been blowing to allow cool waters to mix in. Scientists think the warming trend will continue.

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