The main front of a storm system that is expected to be the final one for at least a week powered through the Bay Area early Thursday, bringing slow, steady rain that is expected to give way to scattered showers as the day progresses.
Its primary impact, more so even then the rain, might be what it will do to the ocean waves, the National Weather Service said.
“In the wake of this system and the one that preceded it earlier this week, the waves are really going to build up,” NWS meteorologist Brayden Murdock said. “We’re gonna have a good chance to see some 20-foot breakers, and a longer-period chance for sneaker waves.”
The weather service said a beach hazards statement will go into effect along the Pacific Coast beginning at 4 p.m. and will continue through 10 p.m. Monday. Most waves are expected to break between 13 and 18 feet.
As for the rain, it continued to soak an already saturated region. The storm system was the fourth to pass through the region since the start of November, though the weather service said it’s the least powerful of them. Murdock said the main front hit the North Bay around 9 p.m. Wednesday and became more widespread through Thursday morning.
By 7 a.m. Thursday, it was slowly moving east and south, putting areas such as Walnut Creek and Hayward in the East Bay and San Jose in the South Bay on target for more rain later Thursday, Murdock said. The upper-surface low pressure also continues to influence things, he said, and as it moves in, that will created the scattered showers.
“It’s going to be very scattered,” he said. “The cloud cover will try to lift and you may see it get a big higher, but it won’t lift entirely.”
Overnight, the weather service measured about four-tenths of an inch of rain in downtown Oakland, Union City, Hayward and Richmond. They measured a quarter-inch at both San Jose Mineta International Airport and San Francisco International Airport, as well as Ben Lomond in the Santa Cruz Mountains. Concord received five-hundredths of an inch.
“It’s going to be very spotty by the time we get to Thursday night,” Murdock said of the rain. “By late Thursday, it clears up entirely.”
It should stay clear for at least a week, according to the weather service. High temperatures will remain in the low 60s and high 50s in the warmest places.