Big south swell could produce 10 foot waves at San Diego beaches

A storm that originated off New Zealand and sent historically large waves to Tahiti and Hawaii will produce breakers in the 4 to 7 foot level, with sets up to 10 feet, at some San Diego County beaches through early Thursday, according to the National Weather Service.

The swell began to roll ashore on Monday, generating waves up to 8 feet at Mission Beach and up to 5 feet at Solana Beach. The weather service later adjusted its forecast to accommodate larger sets.

"The time between wave peaks has been up to 20 seconds, which is the longest period I've seen in years," said Mark Moede, a weather service forecaster. "That shows that this is a swell from the southern hemisphere."

Surfline.com and other surf outlets reported that the swell first produced massive waves last week at Teahupoo, Tahiti, which is widely considered to be one of the most dangerous surf spots in the world. The swell rolled on and generated surf that reached 25 feet over the weekend in the Diamond Head area of Oahu, Hawaii. KHON-TV said the waves were the largest to hit that area in more than 25 years.

Moede said that San Diego County beaches that face the southwest will take the biggest beating from the incoming swell. Dangerous rip currents are expected up and down the coast.