An early spring storm off the coast of Maine is expected to pummel some parts of the state with as much as a foot of snow before it leaves the region Monday afternoon.

Portland could be in line to get 3-6 inches of snow, while parts of Down East Maine could see anywhere from 10 to 12 inches, according to the National Weather Service in Gray.

Sunday was the first day of spring, and Portland has received just a half inch of snow so far this month.

Margaret Curtis, a meteorologist with the National Weather Service, said Portland and coastal communities are on the outer edge of the 500-mile-wide ocean storm, a situation that has produced a variation in forecasts. WCSH-TV, for instance, was forecasting 1-3 inches of snow in Portland on Monday.

“We are right on the edge and that’s making this storm a nail-biter,” Curtis said. “You are looking at something that is very big and a small wobble (in its track) could make a big difference in how much snow a town gets.”

Curtis said snowfall amounts in Cape Elizabeth could be much higher than snow accumulation in Westbrook. She said the farther inland one goes, the smaller the snowfall amounts will be, with Fryeburg projected to get 1 inch. The heaviest snowfall should be in Rockland and areas Down East. Rockland is forecast to receive 6-8 inches while places like Calais and Machias are facing a possibility of 7-12 inches.

Curtis said Monday’s storm should not break any records for Portland. The previous snowfall record for March 21 was 10.8 inches set in 1992. Curtis said it’s “not completely out of the question,” that Monday’s storm could completely miss Portland.

Down East Maine was placed under a winter storm watch Sunday evening by the National Weather Service. A watch means there is a potential for significant snow, sleet or ice that could affect travel conditions.

Curtis said it should start snowing sometime after midnight Sunday and continue through the early morning hours, making the morning commute a bit treacherous in Portland. The storm should move out of the Portland region by midafternoon.