A moisture-rich and cold storm will continue to bring snow to the West today. Up to an additional foot of snow will fall in the northern Sierra Nevada.
While somewhat lesser amounts will fall at pass levels, the snow will fall at a fast and furious pace and has the potential to close passes, affecting portions of I-80 in California and Nevada and I-5 in California and Oregon.
According to Western Weather Expert Ken Clark, "Snow levels will dip to around 500 feet in the hills around Seattle and Portland, trending to near 3,000 in the central Sierra Nevada."
This means snow will mix in around these elevations with accumulations trending upward above this level throughout the Olympics, Cascades and northern and central Sierra Nevada.
The snow will be powdery in nature in the mountains, subject to a great amount of blowing and drifting by strong winds. Whiteout conditions are likely at times.
What poses difficulties for travelers will be a boost for the ski industry and water interests. Unlike last winter, storms have been scarce.
As the moisture pushes farther inland today, locations along the coast will see precipitation that is more showery in nature.
While much less rain will fall over the Sacramento Valley, any non-destructive rainfall will be welcomed.
No significant precipitation is forecast for Southern California and the deserts with this storm, unlike the system to start this week.
However, heavy snow will progress eastward through the Wasatch and various ranges over the central and northern Rockies today.
Dry and sunny conditions will continue in San Francisco for the the official start to winter and the Christmas holiday.
Sunshine will return in full force for the weekend, the official start to winter, and Christmas in Los Angeles.
Big changes are on the way for parts of the Western and Central states late this week and into this weekend.
Similar to the days prior to Thanksgiving, the worst weather will focus on the days prior to Christmas as millions of travelers take to the roads and skies in the U.S. and southern Canada.
Warm air is forecast to surge into much of the eastern half of the nation by the weekend and will be accompanied by heavy rain and flooding risk in some locations.
Thunderstorms in parts of the South this weekend may become strong enough to threaten lives and property.
West Palm Beach, FL (1989)
Record high of 88 degrees.
SW Arkansas (1967)
A 200 mile wide tornado killed people along its 15 mile path from Waldo to near Bueana Vista. People from one house were carried 250 yards and cars were said to have been carried 600 yards.
Philadelphia, PA (1991)
High of 30 degrees; only 5th day in 1991 with a high below freezing.