Will it Snow?

If you’re lucky this weekend, you’ll stick out your tongue and catch a snowflake.

Low-falling snow may tempt our Mediterranean-climate-loving selves to play hooky on Friday, Bay Area meteorologists are saying.

From the Santa Cruz Mountains to the Mt. Diablo range, from Sonoma Mountain to Mount Madonna, meteorologists predict snow will falling on  anything above 1,000 feet Thursday night.

By Friday night, scattered precipitation could deliver snow at sea level in some spots—depending on when the really cold temperatures arrive.

“It has to be the right combination of factors, in just the right sequence,” said Jan Null meteorologist with Golden Gate Weather Service. “First, you need the cold air, then the precipitation, not just cold rain.”

The National Weather service is predicting rain showers for South San Francisco, but we can dream.

The last time just the right combination came together was Feb. 5, 1976, when a broad cold front brought snow all over the Bay Area 35 years ago. Before that, Jan. 15, 1962, that brought less than an inch, just a few months after our president was born.

The heaviest precipitation arrives to the Bay Area on Thursday and is predicted to be over before very cold air arrives that would bring snow lower. The best guess is only a 50:50 chance, but you never know in the weather business.

“The temperatures are going to be bigger story after that,” said Null. He expects a hard freeze on Saturday morning to Sunday, with lots of 20-degree readings across the bay.

Still, on Friday morning you could very well see Mt. Tam —at 2,400 feet—quite covered with snow, Null said.

-    Skyline Road in the East Bay hills—at 1,000 feet—

-    Mission Peak—at 2,200 feet—

-    Mt. Diablo— at 1,900 feet—

-    Mt. Madonna–at 1,800 feet—

-    Santa Cruz Mountains—from 1,000 to 3,000 feet—

-    Sonoma Mountain—at 2,400 feet—

A snowy tableau is a powerful magnet. That’s how sheriffs deputies find the flatlanders heading for the hills to flex their snowball-throwing muscles…and getting their vehicles stuck when they pull off the road in the snow to play. 

It also is treacherous for those who don’t have snowman-building-with-the-family on the agenda. 

“We recommend you have a back-up plan if you go over mountains for your commute,” said National Weather Service meteorologist Steve Anderson.

If driving conditions are hazardous, Caltrans often shuts down Hwy 17 between Santa Cruz and Silicon Valley. Ditto for Mt. Hamilton rising on the opposite range above Silicon Valley. Authorities shut the gate at Mt. Diablo Junction leading to Mt. Diablo.

Anderson just shakes his head when it comes to Sonoma County. “It's just going to be a mess Friday morning,” he said. “People will be trying to get over mountains and they won't be able to get over.” 

If snow falls in South San Francisco, post your photos on this story or email them to drew@patch.com. Everyone who sends in a photo get a Patch tote bag!