HALIFAX—A powerful winter storm swept across the Maritimes on Saturday, blanketing much of the region in heavy, blowing snow and causing road closures, power outages and widespread cancellations. Drivers were urged to avoid travel amid blizzard-like conditions, and many roads and highways—including the border between Nova Scotia and New Brunswick—were closed to traffic. A flurry of closures were announced throughout the day in Nova Scotia, Prince Edward Island and New Brunswick, including universities, libraries, COVID-19 clinics and businesses. Flights, ferries and public transit were also delayed or cancelled due to weather. The changeover from snow to freezing rain with high winds created the perfect storm for potential power failures, retired Environment Canada meteorologist Jim Abraham said. He said freezing rain can stick to power lines and tree limbs, making them heavier and more susceptible to breaking as the winds pick up with gusts as high as 100 km/h in the …