Several more days of dense fog, driven by a deep marine layer, are expected across Los Angeles, an unusual weather pattern for this time of year that is bringing significant cooling to the region.
“It’s kind of more like a June pattern than it is a September pattern,” said Mike Wofford, a National Weather Service meteorologist in Oxnard. And “we’re expecting not a lot of change the next few days.”
A low-pressure system spinning off the coast has created a strong onshore flow across Southern and Central California, bringing clouds and cooler temperatures from the Pacific, Wofford said. He said this development is not unheard of for September, but more typical in late spring and summer.
“It’s generating a deeper marine layer, that’s even getting into the valleys,” he said. By mid-morning, most of the valleys will see clearing, but some of the area’s beaches could remain foggy all day, he said.
The pattern brought some drizzling to parts of Los Angeles early Wednesday morning, Wofford said, but not much more precipitation is expected — though it’s always possible.
“Anytime you have the clouds there like that, you could get a spotty drizzle,” Wofford said. “It’s not going to get to the point where [the marine layer is] super deep and it generates [significant] rainfall.”
The clouds, however, have dropped temperatures about 10 degrees compared to earlier this week, Wofford said.
The cooler weather pattern comes after a heat wave baked the region in early September, bringing triple-digit temperatures and fueling several wildfires, before cooling off temporarily over the past week.
“It’s cooler than typical,” he said. The coast is expected to top out the rest of the week in the 60s and low 70s, while the valleys should stay in the 80s — well below average for this time of year.
And the forecast shows this trend won’t budge until early next week, Wofford said.
“Somewhere around Tuesday … it is a little bit weaker onshore flow and we’ll probably see some warming next week,” he said.