Weekend storm's unusual winds could cause power outages

A pedestrian crosses at the corner of Palm and Morro streets in San Luis Obispo under rainy skies on Wednesday.
A pedestrian crosses at the corner of Palm and Morro streets in San Luis Obispo under rainy skies on Wednesday. dmiddlecamp@thetribunenews.com

More stormy weather that is expected into the weekend for San Luis Obispo County will bring not only rain, but also the potential for pounding surf and gusty conditions, including a wind event that is rare for the area, forecasters say.

The steady rain of Wednesday will turn to showers Thursday before there is a break in storms, PG&E meteorologist John Lindsey said. He said the next cold front will arrive Friday night with winds that will gust on the coast up to 45 mph.

Showers will linger into Saturday, and then the wettest storm of the series will arrive in northern San Luis Obispo County later that night and produce heavy rain as far south as Cambria, Lindsey said. Moderate to heavy rain will spread over the rest of the region by Sunday morning.

This storm will also pack unusual winds, Lindsey said.

Typically in San Luis Obispo County, winds blow from the northwest. When storms occur, winds usually shift and come out of the southeast. But Sunday, the storm will blow out of the southwest and be strong, with gusts up to nearly 60 mph on the coast.

“I can count on my hand the number of times there has been a big southwesterly wind event,” said Lindsey, who has more than two decades of forecasting experience on the Central Coast. “It is pretty rare, seldom seen.”

The cause, Lindsey said, is this: Low pressure over Northern California will intensify and move eastward over Nevada. At the same time, an area of high pressure will be 500 miles west of San Luis Obispo County. The resulting interaction of the two will create winds from the southwest, which will start blowing Sunday morning.

One result could be power outages, Lindsey warned.

“Tree limbs get used to one direction of wind. When it comes out of a direction that is unusual, limbs will be more likely to break off,” he said.

The ocean swell will also come from the west. A high-surf advisory has been issued by the National Weather Service for Thursday through Sunday night.

“Surf of 10 to 15 feet can be expected with local sets to 20 feet possible,” the weather service said in the advisory, with the highest surf likely around Morro Bay.

Lindsey expects waves to be more in the 11- to 13-foot range, though individual sets of 20 feet could be possible. He said Port San Luis could be most vulnerable.

By Monday, Lindsey said San Luis Obispo should have received between 2 to 4 inches of rain.