Over the past several weeks, Northern California has been on a weather roller coaster, with a series of weak late-season storms interrupting the periods of hot, dry weather that are more typical of June.
Case in point: After last week’s mini heat wave sent inland temperatures soaring into the 100s, a storm system from the Pacific Northwest delivered a potent dose of cold and thunderstorms to the mountains and farthest reaches of the Golden State, especially along the coast.
The rain was heavy enough to trigger mudslides in the Dixie Fire burn scar across Butte and Plumas counties, closing a stretch of Highway 70. The National Weather Service’s Sacramento office issued a flash flood warning ahead of the rain and said that 1 to 3 inches of rain fell over portions of Plumas County between noon and 6 p.m. Sunday.
And here we go again. A warm-up is baking interior Northern California this week with temperatures expected to peak in the mid- to high 90s on Wednesday. But the heat won’t last long, with a trough of low pressure slated to push into Northern California on Friday into Sunday.
While this system originating in the Gulf of Alaska isn’t expected to deliver as much rain as the last storm, there’s a possibility of light snow in the highest elevations of the Sierra Nevada and thunderstorms north of Interstate 80, especially in the far northern Sacramento Valley and the mountains of Shasta County and far northern Tehama County, the weather service said.
“This one doesn’t have the same dynamics or instability as the last system, but on Friday and Saturday there will be some chance of thunderstorms,” said Cory Mueller, a forecaster with the weather service’s Sacramento office. “It’s fairly unusual for this time of year to see these troughs coming down. They’re not dropping a ton of rain but that’s the way it is in June with these systems.”
The Tahoe Basin is expected to see some vast temperature drops this week with afternoon highs on Saturday as much as 20 degrees lower than they were on Wednesday. South Lake Tahoe is predicted to hit a high of 76 today and a high of 56 on Saturday.
The weather pattern has mostly resulted in significant temperature fluctuations for the Bay Area as well as some late-season light rain and drizzle, mostly along coastal mountains and in the North Bay.
With this upcoming system, the Bay Area isn’t expected to see any rain, but temperatures will drop. The mercury is forecast to push into the 90s in inland areas of the region on Wednesday, and begin to drop on Thursday.
“Breezy onshore winds overnight into Thursday will allow for much cooler temperatures on Thursday with highs down into the 70s for inland areas,” the weather service’s Bay Area office said in its forecast. “Friday looks to be the coolest day of the week with highs only in the upper 60s and lower 70s regionwide with unseasonably cool upper trough in the vicinity of Cape Mendocino.”
