A Nor'easter has begun to slam most of Nova Scotia, dumping swirling snow up the Atlantic coastline.

Forecasters are predicting 15 to 25 centimetres of snow will pile up by Thursday morning.

The storm started after noon and is expected to continue until midnight. The wind will peak Wednesday evening causing blowing and drifting snow.

CBC meteorologist Kalin Mitchell says the snow will be heavy, making it harder to shovel.

He said the snow could mix with ice pellets along the coast from Yarmouth to Halifax.

His colleague Peter Coade said the temperatures will continue to be below normal for this time of year.

There are a handful of cancellations and delays at the Halifax Stanfield International Airport.

Air Canada has issued flight warnings about several North American airports.

Dalhousie, University of King's College and the Nova Scotia College of Art and Design also closed early on Wednesday due to the storm. 

The wind is expected to diminish by Thursday morning.

Wednesday's storm will mark the third midweek clobbering in a row.