A student crosses campus through the snow at the University of Maine in Orono, April 3, 2019. A storm moving into Maine on Monday could drop up to 5 inches over Greater Bangor. Credit: Linda Coan O'Kresik

A significant storm moving into Maine overnight could bring heavy snow to parts of the state in time for the morning commute.

The National Weather Service has placed central and northern Maine as well as the western mountains under a winter storm watch in effect from Monday morning to Monday evening.

“Travel could be very difficult. The hazardous conditions could impact the Monday morning and evening commute,” the weather service said in an alert Sunday morning.

Snow will start to fly by 7 a.m. over Greater Bangor, where up to 5 inches of snow are expected to fall, according to the weather service office in Caribou. A wintry mix is expected along the Down East coast, where 3 to 5 inches could accumulate from Bar Harbor to Eastport. Inland Washington County could see higher snowfall, with 6 inches possible in Calais and 8 inches in Danforth.

Heavier accumulation is expected in Piscataquis and northern Penobscot counties, where up to 9 inches is forecast for Greenville and Millinocket and up to 8 inches in Lincoln, according to the weather service.

Up to half a foot of snow could fall across much of northern Aroostook County from Presque Isle to Madawaska, according to the weather service. The heaviest snowfall in The County is expected near Houlton, where up to 8 inches is forecast to fall Monday.

It was a snowy winter along the crown of Maine. Caribou has had continuous snow cover since Nov. 10, 2018, and 23 inches of snow remain on the ground in a region that has seen 158.5 inches over the course of the season, according to the weather service. The new snowfall on Monday could push that total into third place behind 1955 and 2008, the weather service said.

Southern Maine will be spared the heaviest of the snow, with less than an inch expected along the immediate coast and 1 to 3 inches further inland, according to Dustin Bonk, a meteorologist for CBS affiliate WGME in Portland.

What snow falls in the southern part of the state will mix with rain and likely melt quickly, according to WGME.

Highs on Monday will range from the high 20s in the north to the low 40s in the south. The wet weather is expected to stick around the state until Wednesday before giving way to sunny skies and temperatures in the 40s throughout the state Thursday, according to the weather service.