* WHAT...South winds 25 to 35 mph with gusts up to 60 mph possible. * WHERE...Carquinez Strait and Delta, Sacramento Valley, Motherlode, Northeast Foothills, and Northern San Joaquin Valley. * WHEN...From Tuesday afternoon through Friday afternoon. * IMPACTS...Strong winds and saturated soils could blow down trees and power lines resulting in widespread power outages. Strong winds may cause impacts to unsecured items, including temporary structures and holiday decorations. Travel could be difficult, especially for high profile vehicles. * ADDITIONAL DETAILS...Strongest wind gusts expected in the northern Sacramento Valley and adjacent foothills on Wednesday.

* WHAT...Heavy snow expected. Accumulations up to a foot between 4500 to 5500 feet. 4 to 8 feet, with locally higher amounts above 5500 feet. Wind gusts up to 60 mph. * WHERE...West Slope Northern Sierra Nevada and Western Plumas County/Lassen Park Counties. * WHEN...From 10 PM Tuesday to 10 PM PST Friday. * IMPACTS...Dangerous travel conditions with chain controls and road closures. Localized tree damage, power outages, and low visibility due to the combination of heavy wet snow and strong winds. * ADDITIONAL DETAILS...Snow accumulations will remain near or above pass level through Tuesday, then drop to around 4500 to 5500 feet during the day Wednesday through Friday. Snowfall rates of 1 to 2 inches per hour at times.

* WHAT...Heavy snow possible. Accumulation amounts uncertain at this time but may range from around a foot at 5500 feet and 3 to 6 feet with locally higher amounts at 6500 feet and above. Winds could gust as high as 55 mph. * WHERE...West Slope Northern Sierra Nevada and Western Plumas County/Lassen Park including Interstate 80 and Highway 50. * WHEN...From Tuesday evening through Friday morning. * IMPACTS...Dangerous travel conditions with chain controls and road closures possible. Low visibility due to combination of wind and heavy snow. * ADDITIONAL DETAILS...Snow accumulations will remain near or above pass level through Tuesday, then drop to around 5500 feet during the day Wednesday.

A series of warm atmospheric rivers will bring moderate to heavy rain to the Valley, foothills, and mountains the week of Christmas. The prolonged period of rain will bring the risk of flooding to the Sacramento Valley, northern San Joaquin Valley, northern Sierra Nevada and adjacent foothills, as well as the Coastal Range. * WHAT...Flooding caused by excessive rainfall continues to be possible. * WHERE...A portion of northern California, including the following areas, the Sacramento Valley, northern San Joaquin Valley, Delta region, Sierra Nevada and adjacent foothills, and Coastal Range. * WHEN...Through Friday afternoon. * IMPACTS...Excessive runoff will result in rises along area rivers, creeks, streams. Small streams and creeks may rise out of their banks. Flooding may occur in low-lying, poor drainage, and urban areas. Mudslides and rockslides may occur in mountain and foothill areas. * ADDITIONAL DETAILS... - Periods of moderate to heavy rain are forecast the week of Christmas. Debris flows are not expected over recent burn scars, but do anticipate enhanced runoff in/below scars. - http://www.weather.gov/safety/flood