Environment Canada said the intense nor'easter brought nearly 40 centimetres of snow to parts of southern New Brunswick, while about 15 to 20 centimetres was forecast for Prince Edward Island by Sunday evening.
About 20 centimetres of snow was expected to fall in northern Nova Scotia and blowing snow warnings were issued for much of the province.
Meteorologist Andy Firth said the snow changed to rain in Halifax northeast to New Glasgow as the day went on, but it then changed back to snow as the low pressure system tracked toward Cape Breton.
"It's a little closer to the coast than what was originally expected so it's a bit stronger low (pressure system) than what was originally expected," Firth said from Dartmouth on Sunday.
"When it goes by, temperatures cool off really quick and the blowing snow starts up and it gets kind of nasty again."
Firth said the western tip of Nova Scotia experienced blowing snow with wind gusts up to 80 km/h, while snow squall warnings were in effect for western Cape Breton overnight Sunday and on Monday.
Storm surge warnings had also been issued for northern Nova Scotia and along the southern Gulf of St. Lawrence, where high water levels and strong winds were expected to produce pounding surf.
About 1,000 customers in western Nova Scotia and another 1,500 in central areas of the province were without power Sunday afternoon.
In New Brunswick, about 1,400 people were waiting for their power to be restored in Bouctouche mid-day, while about another 1,500 were in the dark in Moncton, Sackville and Shediac Sunday evening.
The storm grounded flights at Halifax Stanfield International Airport Sunday morning, with delays and cancellations continuing throughout the day.
It was also to blame for several flight cancellations and delays at St. John's International Airport and the Greater Moncton International Airport.
Arrivals from some major Canadian airports — like Toronto Pearson International Airport — to Halifax, Moncton, Saint John and Fredericton were also either delayed or cancelled Sunday.
Halifax airport spokesman Peter Spurway said the delays could continue into Monday and urged travellers to check on the status of their flights before heading to the airport.
Public transit in Moncton, N.B., came to a halt Sunday, as Codiac Transpo suspended its service. Buses were set to resume Monday.
A bus bound for Charlottetown slid off the road near Summerside and landed on its side late Sunday afternoon but there were no serious injuries. Police were not in a position to immediatley say if weather was a factor.
High winds on the Cabot Strait caused Marine Atlantic to cancel ferry crossings between Port Aux Basques, N.L., and North Sydney, N.S., on Sunday.
Traffic on the Confederation Bridge between New Brunswick and P.E.I. was restricted for vehicles including motorcycles, cars towing trailers, trucks, tractor trailers and buses due to high winds.
Areas of central new New Brunswick — like Fredericton and Gagetown — had just finished digging out of a storm late last week that dumped between 20 and 40 centimetres of snow. As much as 20 centimetres fell in those areas on Sunday.
The storm was expected to hit Newfoundland and Labrador on Monday, with snowfall amounts ranging from 10 to 15 centimetres in southern Newfoundland to as much as 45 centimetres in eastern Labrador.
Parts of northwestern and southern Newfoundland were bracing for winds gusting from 100 km/h to 140 km/h.
Meanwhile, a separate storm was bringing heavy snowfall and high winds to eastern Quebec on Sunday. Forecasts said areas like Gaspesie and Iles de la Madeleine could get between 15 and 40 centimetres of snow by Monday morning.
Note to readers: This is a corrected story. A previous version wrongly said the Confederation Bridge is between Nova Scotia and PEI.
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