A person shovels out a vehicle parked on the Eastern Promenade in Portland on Feb. 9. Shawn Patrick Ouellette/Portland Press Herald

A winter storm lasting more than 24 hours this weekend is expected to deliver a sampling of everything to southern Maine: snow, sleet and freezing rain.

“It’s all one kind of system. It’s a long-duration one,” said Greg Cornwell, a meteorologist at the National Weather Service in Gray.

The storm started with snow Saturday evening, with Cornwell forecasting that the snow will switch to freezing rain and sleet at some point Sunday. The forecast is less than clear about when the system will change from snow to freezing rain: “It gets a little muddy if warm air comes in, then sleet and freezing rain,” Cornwell said.

Everyone from those who have to shovel their driveways to children hoping to enjoy fresh snow on a holiday weekend will be watching how many inches of snow the storm will leave behind, but the weather system is likely to bring more than just fresh powder.

“Accumulated sleet is kind of an odd thing to walk on and shovel,” Cornwell said. “It’s kind of granular and doesn’t behave like snow packed down.”

“We’re confident it’s going to be an impactful winter storm for the region, but there are still details to be ironed out for snowfall or freezing rain,” he added.

Snow is expected to continue into Sunday afternoon, followed by sleet between 2 and 5 p.m., then freezing rain and more sleet. Snow and sleet accumulation of 3 to 7 inches is possible.

The totals are expected to be greater in northern and central Maine. The National Weather Service expects snow to spread across the region Saturday evening, with the potential for 8-12 inches across much of central Maine, including the Augusta and Lewiston areas. Parts of western Maine near Rangeley could see 10-16 inches.

Forecasters expected the storm in southern Maine to taper off late Sunday night and move north. “Far southern Maine will be out of consistent precipitation by midnight Sunday,” Cornwell said.

Monday, Presidents Day, is expected to be windy and blustery as the storm exits southern Maine.

Unlike previous storms that brought light, fluffy snow easily shoveled out of the way, the coming storm will have more moisture, Cornwell said.

This winter is shaping up to be more of a resurgence of normal weather after three years of milder, less snowy seasons. Before a storm Thursday that dropped between 10 and 12 inches of snow, Portland had nearly reached last year’s total for the season.

After Sunday, southern Maine is likely to be on pace for its snowiest winter since 2017-18, according to a meteorologist at the National Weather Service said.