It's been more than three decades since there has been a snowfall in downtown San Francisco, and there is a possibility that this long streak will be broken tonight.
Lower elevations around Los Angeles, as well as other parts of California and the Southwest where it rarely snows, could also have snowflakes flying this weekend. People in areas around Las Vegas could even see snowflakes.
In some places, the snow will be heavy enough to significantly disrupt or even shut down travel.
Snow already made an appearance in some of the higher elevations around San Francisco with a storm last weekend, and a storm moving in through early this weekend will bring snow to even lower elevations.
This is the same storm brought several inches of snow to Seattle and Portland.
The cold air coming in with this storm has Clark very impressed.
"There indeed could be snow in the San Francisco Bay area and the Central Valley of California Friday afternoon or night," Clark stated, "and a few rain and snow showers Saturday. Snow levels could go down to 1,000 feet in the L.A. Basin Saturday."
In downtown San Francisco, he adds that it is very possible that in a heavy rain shower there could at least be wet snowflakes. It's not a guarantee but it's certainly possible.
There is growing concern that major passes around the San Francisco Bay area will be affected by snow.
In addition to the San Francisco Bay area and some valleys of Southern California, snow could also fall in the Upper Deserts and the heavily-traveled passes of Southern California, including the Grapevine and Cajon Pass.
"Precipitation will end up being all snow above 3,000 feet, or certainly below pass level," Clark said, "so the Grapevine could pick up 6 to 10 inches of snow."
Clark adds that other passes, such as the 14 Freeway from L.A. to the Antelope Valley, will also be affected. He says that even the Antelope Valley itself could have snow.
Snow along Interstate 40 into Arizona could become a major problem as well.
The last time it snowed in downtown San Francisco was on Feb. 5, 1976, when 1 inch of snow was measured.
For more details on the storm and what to expect at different elevations across California, refer to Clark's blog.
Photo courtesy of Photos.com
Several storms will bring periods of rain and gusty winds to the west coast of the United States next week with the potential for one of these to reach Southern California.
Colder weather, and in some cases, a taste of winter with snow will continue to invade the northeastern United States this weekend.
Dry weather set to dominate the southern United States into November will only worsen the already extreme drought conditions.
The changing of the seasons will bring beneficial rainfall to northern Brazil, a region that has experienced severe drought over the past several years.
Rain will continue to cause travel delays and raise the risk of isolated flooding in parts of the northeastern United States and Atlantic Canada into Saturday evening.
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No rain from August 28-October 22. Severe drought throughout Southeast.
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