HALIFAX -- Hazardous conditions were expected in parts of the Maritimes on Wednesday as a powerful nor'easter was poised to sweep up from Maine through the region with powerful gusts and a messy mix of snow, ice pellets and rain.

Environment Canada said the storm was likely to dump between 20 to 30 centimetres of snow throughout New Brunswick beginning on Tuesday evening and into Wednesday.

Lesser amounts of snow are expected in Nova Scotia and Prince Edward Island, but the blasts of wind are still expected to reach up to 80 to 90 kilometres per hour.

The weather conditions were already causing power outages across Nova Scotia and New Brunswick early Wednesday.

Nova Scotia Power was reporting more than 36,000 customers were without electricity, while NB Power reported almost 3,500 outages.

Environment Canada has noted that the rapid accumulation of snow was likely to make travel difficult in many locations, with visibility suddenly reducing to zero when wind speeds pick up.

The snow may change to rain over southern and eastern areas of the region on Wednesday morning, with a few hours of ice pellets or freezing rain likely during the precipitation changeover.

Jean-Marc Couturier, a forecaster with Environment Canada, said some coastal areas will receive 30 to 40 millimetres of rain.

"It's been very cold lately, so the ground surface is frozen and there will be a lot of run-off and some localized flooding," he said. "It's another problem we will face."

The Halifax airport was showing multiple flight cancellations across its arrival and departure board for Tuesday night and into the early hours of the morning.

Couturier said it's possible that another disturbance could hit southern parts of the Maritimes on the weekend, as winter continues to hang on through mid-March.

"We're far from done," he said.