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.

Those areas have been placed under a flood watch through Friday, Dec. 26.

The National Weather Service in Sacramento has issued the flood watch from 4 p.m. Saturday, Dec. 20 through 4 p.m. Friday, Dec. 26.

Flooding caused by excessive rainfall is possible.

Excessive runoff will result in rises along area rivers, creeks, and 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.

Periods of moderate to heavy rain are forecast the week of Christmas, according to the National Weather Service. Debris flows are not expected over recent burn scars, but officials do anticipate enhanced runoff in/below scars.

For more information, visit http://www.weather.gov/safety/flood

Residents are advised to monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.