A month that already has been a soaking wet one in the Bay Area is about to take on some more rain this weekend, according to the National Weather Service. The real question is how much more saturated areas of an already wet region will become?
“These are the tail end of the big system that’s moving through the north,” NWS meteorologist Rick Canepa said. “So you’re seeing the weak side of the surface low pressure as it approaches Northern California and our area. There’s some good water vapor higher up, so you might see a lot more in the higher elevations.”
In other words, those who live near Mount Tamalpais and other areas of the North Bay where rain typically falls hard should batten down the hatches. Residents who are in the East Bay and Peninsula can probably gear for a bit less. And the population of the South Bay near San Jose may not see a speck.
Whatever rain does fall only will add to what already has been a significantly wet October.
All of it is being created by what the weather service has called a small atmospheric river that’s migrating from off the northern coast. The major impact of that system will land on Oregon and far Northern California, Canepa said. But there will be plenty left over to dump what is expected to be an inch in the North Bay and up to a quarter-inch closer to Contra Costa, Alameda and San Mateo counties.
A second small wave from the tail end of the system is also anticipated to drop a bit more rain on Sunday night and possibly into Monday.
“it’s likely to be highly variable,” Canepa said. “In a way, these kind of events can be really tough to forecast. It’s the tail end of the this system, but that tail end could carry some decent precipitation.”
The pending arrival of the rain was preceded by some dense fog in the interior valleys of the North Bay, with visibility early Friday dipping to a quarter-mile. That fog was expected to burn off by later Friday morning.
The weather service also said that conditions at Bay Area beaches were expected to be more dangerous. A beach hazards statement went into effect at 3 a.m. Friday and will last until 3 a.m. Monday. Waves are expected to break at 15-20 feet and rip currents are expected to be sneaky strong.
The entire system is expected to be through the region by Monday morning, and gradual clearing from the cloudy days is expected to take place into early next week, and temperatures are expected to climb toward their seasonal average.