As the threat of another big snowfall emerged Sunday, schools throughout southern Maine acted quickly to cancel Monday’s scheduled classes.

By Sunday night, Berwick Academy and school departments in Biddeford, Saco, Old Orchard Beach, Eliot, Waterboro, Kennebunkport and Kennebunk were among those that decided it would be too dangerous for students to be on the road Monday morning during the most intense part of an extended snowstorm.

Schools across southern Maine followed suit with delays and cancellations, including Portland, Cape Elizabeth, New Gloucester and midcoast towns of Brunswick and Damariscotta. For a complete list of delays and cancellations, click here.

Stacie Hanes, a meteorologist with the National Weather Service in Gray, said southern New Hampshire and York County would feel the brunt of Monday’s snow accumulation, with the forecast calling for the region to get 10 to 14 inches of snow.

“It’s not really one storm,” Hanes said. “It’s a series of low-pressure disturbances moving across the region. It’s a prolonged snowy period that will produce pulses of snow.”

The snow started falling late Saturday night and continued into Sunday. Portland received 1.9 inches of snow Sunday, and Kittery Point in York County got 2.7 inches. Those snowfall amounts should increase substantially Monday morning when the snow is expected to intensify, dropping an estimated 6 to 10 inches in York and Cumberland counties.

By the time it stops snowing early Tuesday, Portland should end up with  9 to 10 inches of snow, with midcoast communities such as Brunswick in line for about 8 to 10 inches, Hanes said.

“Monday morning is when we are going to see the heavy stuff, with the snow beginning to taper off by late Monday afternoon,” Hanes said.

The National Weather Service issued a warning Sunday night that “roads will remain snow-covered and slippery. Additional snow will continue to add weight to any heavily covered roofs. Snowbanks will continue to get larger, perhaps impeding vision when (cars are) turning into roadways.”

The weather service advised motorists to drive with their headlights on during daytime hours, a step it says could alert other drivers to cars emerging from driveways or intersections that have been blocked by gigantic snowbanks.

On Sunday morning, with yet another snowstorm on the way, Portland officials issued safety reminders to residents, asking them to set out trash in the early morning rather than at night to make plowing easier for road crews, to abide by city parking bans, and to use caution when driving near towering snowbanks. There was no parking ban in effect Sunday night.

Jessica Grondin, the city’s spokeswoman, said any residents who must remove snow from their roofs should use caution and follow proper safety protocols. Grondin said using a long-handled snow rake is always preferred over using a ladder to gain access to a roof. She said people should never shovel snow or rake snow from roofs while alone.

In the York County town of Limerick, a man who was shoveling his roof Sunday morning fell about 10 feet to the ground. It was not clear whether he was already on the roof or climbing a ladder to get to it. The accident took place around 10:43 a.m. at 44 Johnson Road.

Assistant Fire Chief Jason Johnson said the man was transported by ambulance to Maine Medical Center in Portland. Johnson did not know the extent of his injuries.

On Sunday, temperatures reached a high of 22 degrees in Portland with single digits in the north and the mountains. Temperatures overnight were expected to dip to 10 to 12 degrees in Portland and near zero to the north and mountains. The high in Portland on Monday could reach 15 to 17 degrees.

The storm systems should move out Tuesday morning and sun could reappear later in the day. Tuesday and Wednesday should be good days to get out and about.

But Hanes said there is a possibility for more snow Thursday. She said that storm could miss Maine depending on the track it takes.

“There is a 30 to 50 percent chance that we will get more snow on Thursday,” she said.

Speeds on the Maine Turnpike were reduced to 45 mph Sunday. Several minor crashes were reported Sunday morning, including a two-car crash in the northbound lanes between exits 7 and 19 at 10 a.m. and a one-vehicle crash near exit 42 in the southbound lanes.

Maine State Police reported several slide-offs late Sunday, but no serious motor vehicle accidents.