A woman struggles through blowing snow while crossing Middle Street in Portland on Tuesday.

Another nor’easter is expected to arrive in Maine late this morning, delivering a foot and a half of heavy snow — or more, in some places — and stiff winds over the course of Tuesday and Wednesday.

The National Weather Service on Tuesday morning issued a blizzard warning for the entire Maine coast until Wednesday morning, saying winds could gust as high as 55 mph in southern and midcoast Maine, and as high as 45 mph east of Penobscot Bay. The entire state is under a winter storm warning.

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“The snow will become heavy at times late this morning and winds will rapidly increase in coastal sections early this afternoon into this evening,” NWS forecasters wrote in the warning. “Blizzard conditions are now expected in coastal Maine and New Hampshire. The heaviest snow and strongest winds will begin to taper off from southwest to northeast beginning this evening.”

Developing out of a low-pressure system off the mid-Atlantic coast, it is the third late-winter storm to blast the state in the last two weeks. Most of the coast, including Portland, and sections of central Maine could get 18 to 24 inches of snow by the time the storm exits the state’s far northeastern corner early Thursday morning.

Between a foot and 18 inches is predicted for the Millinocket area, Washington County, southern Aroostook County, and for most of Oxford and Somerset counties. Bangor also could get between 12 and 18 inches, while northern Aroostook County is expected to get between 6 and 12 inches.

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Schools across Maine have called for early dismissals or closed in anticipation of slippery roads and poor visibility during the Tuesday afternoon commute. Bangor Schools will dismiss students three hours early Tuesday. A number of courts and local government offices also closed Tuesday.

The snow started falling in southern York County just before 8 a.m., said Eric Schwibbs, a forecaster with the weather service in Gray.

It was due to cross the Down East coastline around 10 or 11 a.m., arriving in Bangor shortly thereafter as the storm slowly moves southwest to northeast, added Vic Nouhan, a meteorologist with the weather service in Caribou.

The snowfall will be constant, although it will clobber Maine hardest on Tuesday afternoon. In the hours before nightfall, snow could fall as fast as 2 inches per hour, Nouhan said.

“That’s when the dangerous snow rates will be,” he said, around when people are usually driving home from work.

Strong winds are expected to whip up the snow, limiting visibility and causing heavy drifting, especially along the coast.

“The snow will become heavy at times late this morning and winds will rapidly increase in coastal sections early this afternoon into this evening,” the service warned for people living along the midcoast.

The weather service has warned Mainers to take caution on the roads during that time, when heavy snow could make travel impossible in some places.

The snow will continue through the night, although wane in intensity. The snow on Wednesday is predicted to be lighter, letting up in the early afternoon in Greater Portland and late afternoon in Greater Bangor, forecasters said.

The precipitation could linger in the western mountains until Thursday, although that won’t mean the accumulation totals will be higher, according to Schwibbs.

BDN writer Bill Trotter contributed to this report.

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