By Alex Sosnowski
Senior Meteorologist AccuWeather.com
State College, Pa.
— AccuWeather reports the arctic plunge anticipated last week is aiming for the West first and will drive across California Thursday, Jan. 10.
According to Western Weather Expert Ken Clark, "The coldest air of the season will settle over much of California Friday and Saturday." Temperatures could dip to within a few degrees of the lowest levels reached during all of the prior winter.
Many of the lower elevations in California will have highs ranging from the upper 40s to the middle 50s. Throw in wind and other atmospheric conditions and AccuWeather.com RealFeel® temperatures will be about 10 degrees lower, ranging from the upper 30s to the middle 40s.
Conditions will be much colder in the upper deserts and the mountains. Winds will diminish over much of the state Friday night, paving the way for frost in many locations.
"Some of the valleys in Southern California will dip a little below freezing, but a hard freeze is likely in parts of Ventura and inland Santa Barbara counties," Clark said.
Clark added that while there has been a frost and freeze already over parts of interior Southern California already this season, temperatures in the coldest areas of these counties could be below 28 degrees for several hours during this event. Much of California will struggle to warm Saturday.
"With clear skies and light winds, Saturday night could be almost as cold as Friday night," Clark said.
The initial push of cold air will bring some snow to the Sierra Nevada, but not an exceptional amount of snow. Up to a half a foot of snow will fall over northern areas with perhaps a couple of inches over the central locations.
Enough snow accompanied by plunging temperatures to cause slow travel for at time along I-80 over Donner Pass and I-5 through the Siskiyou Mountains.
While the cold push will only bring a relatively small amount of snow to the Sierra Nevada and the southern Cascades and perhaps a dusting to some of the other ranges in the state, it will help spin up more of a storm and heavier snow farther inland over the West Friday and the northern Plains this weekend.