The National Weather Service office in Medford has issued a variety of statements and advisories warning of snow and extreme cold this week.

Winter weather will continue to pound Southern Oregon as Thanksgiving approaches.

The National Weather Service office in Medford has issued a variety of statements and advisories warning of snow and extreme cold this week.

A fast-moving upper level system is expected to bring another round of low-elevation snow to the region this afternoon and tonight, according to a winter weather advisory issued early this morning. The advisory, which warns of up to three inches of snow at elevations above 1,500 feet, goes into effect at 1 p.m. today and continues through 4 a.m. Tuesday.

Rain will pick up on the coast this afternoon, then precipitation will spread inland by sunset, the advisory said. Snow levels will drop from 2,000 feet to as low as 500 feet overnight. By Tuesday morning, snow will taper off to light showers.

As the storm moves out on Tuesday, another winter weather hazard will arise, a special weather statement explained.

A cold air mass in place over the area combined with clearing skies and fresh snowfall will make Tuesday night an extraordinarily cold one over Southern Oregon and Northern California, the statement said. Temperatures around Medford and Ashland will dip into the teens, nearing record lows, the weather service reported.

Even the coast will see freezing temperatures by Wednesday morning, with forecast lows near 30 degrees. East of the Cascades, temperatures likely will plunge below zero.

The weather service advises people to start preparing for cold weather now by making sure pipes are protected and irrigation systems drained.

In Ashland, a cold-weather shelter will be open tonight and Tuesday night at First Presbyterian Church, on the corner of Siskiyou Boulevard and Walker Avenue. The shelter is open between 8 p.m. and 8 a.m. The shelter probably will be open Wednesday night, too, but the location for that night has not yet been set, organizers said

— Anita Burke