High Tides Due in December

Unusually high tides during December may have a big effect on boaters and people living on the coast, weather officials said Friday.

The San Diego coast will experience high tides of 7.8 feet Dec. 2 and 31 because of a rare alignment of several planets and a full moon, called proxigee, said Wilbur Shigehara, meteorologist at the National Weather Service. The average rise of the tide in San Diego is 5 feet, 9 inches.

“We are going to have some of the highest tides to hit San Diego County for 17 years,” Shigehara said.

The high tides are cause for concern only if they combine with high surf, something the National Weather Service cannot predict so far in advance, Shigehara said.

“Our surf now is averaging about 2 to 3 feet, and if we get a 7.8 high tide, the waves could come in a little higher than normal, but it shouldn’t cause any structural damage,” Shigehara said. “However, if the surf is larger, then we will have some problems.”

The current forecast, which extends to the middle of next week, does not include any threat of high surf, which is caused by strong ocean winds, Shigehara said.

The last time tides reached similar heights was in August, 1987, but they did not coincide with any storms, and little damage was caused, Shigehara said.