Preparations for the storm began early, as airports in the region cancelled dozens of flights in anticipation of the whiteout conditions forecast by meteorologists.
"Through much of the day, the visibility is going to be the biggest concern with prolonged whiteout conditions," said CBC meteorologist Kalin Mitchell.
"Many should expect to see the worst of the blizzard conditions beginning near noon and running into the early evening."
Nearly all other forms of transportation are also being affected. Marine Atlantic has cancelled all of its ferry crossings between Nova Scotia and Newfoundland on Wednesday and Thursday due to high winds and sea conditions.
Maritime Bus, the region's interprovincial bus service, has cancelled all of its runs for Wednesday with the exception of the Halifax airport route, which is scheduled to continue for now.
Transportation officials in all three Maritime provinces urged drivers to stay off the roads whenever possible.
Wind gusts, storm surge expected
The storm is expected to begin between 6 a.m. and 8 a.m. in southwestern Nova Scotia and spread across the province by noon.
By the early afternoon, wind gusts of between 80 and 110 kilometres per hour will be "widespread" across Nova Scotia, said Mitchell.
The snow will begin in the mid to late morning in southern New Brunswick and in eastern P.E.I. By the afternoon, the snow will spread to all corners of both provinces, he said.
"The south and southeast of New Brunswick, as well as western P.E.I., could see snowfall accumulations of 30 to 50 centimetres," said Mitchell.
"In eastern P.E.I., some mixing in of rain is expected late in the day on Wednesday and may keep snowfall amounts slightly lower, but not by much."
Environment Canada said the possibility of damage is real because a storm surge will bring rising waters along the coastlines of Nova Scotia and northeastern New Brunswick — in some cases 50 to 80 centimetres higher than normal, with strong waves driving the sea into shore.
"That is definitely something we have to keep an eye on, especially if it coincides with high tides," said Tracey Talbot, a forecaster with Environment Canada.
"With the storm surge we're expecting, we could see some flooding and some local infrastructure damage."