Another chilly night and morning in the Bay Area led to a freeze warning in parts of the region Christmas morning, according to the National Weather Service.

The NWS issued the warning late Saturday night and it remained in effect until 9 a.m.

Portions of the San Francisco area are expected to see temperatures drop into the 20s and isolated spots could even briefly dip into the upper teens, weather officials said.

Cold and dry airmasses over the area and valleys with mostly clear skies and light wind will lead to lower temperatures, officials said.

The Santa Clara and San Jose-Northern Salinas valleys are expected to be impacted by freezing temperatures, weather officials said.

Cold weather in the East Bay this week has prompted the area's utility district to advise residents to protect pipes from freezing.

East Bay Municipal Utility District officials said customers in the San Ramon Valley have reported difficulty getting water to flow during cold, early mornings.

The utility suggests wrapping exposed pipes with insulating material and discourages opening a faucet to keep water moving in the pipes to prevent freezing. This will only waste water and not keep frozen pipes from cracking or breaking, according to utility officials.