A low pressure system off the coast of Massachusetts is expected to spare Andover and the Merrimack Valley from the worst of a winter storm that could deliver as much as a foot of snow in other parts of the state.

But things will still be ugly in Andover: In addition to as much as an inch of rainfall, a gale warning will go into effect at 4 a.m. Friday and continue until 4 a.m. Saturday for Boston Harbor. In Andover, wind gusts up to 40 mph will roll in tonight and join the rain and be a threat until Saturday morning. If Andover does see any snow this weekend, it will most likely come as a rain-snow mix Saturday morning.

The good news? Once that low pressure system clears out Saturday night, we’ll be left with mostly sunny skies and seasonable temperatures until the middle of next week.

If the forecast changes and Andover does get snow, check the town’s Storm Information Center for updates and alerts. In severe storms, the town can call a snow emergency, which bans parking on all town streets until crews can clear the roads.

The worst of the storm will be in the western part of the state, with a forecast of 8 to 12 inches of snow in North Adams. The northern portions of central Massachusetts are expecting lower snowfall totals, ranging from 1 to 3 inches.

National Grid said Thursday it was calling in external line and forestry crews to address power outages, which could happen throughout the state, thanks to the heavy winds. The utility is urging customers to get their flashlights ready and keep their mobile phones charged for the duration of the storm.

Looking ahead to the holiday, the extended forecast is calling for partly cloudy skies and aa high of 27. Christmas will be cold, with a high of 29, but the current forecast is calling for mostly sunny skies.