The second powerful winter storm to hit the Northeast in a week pounded the region on Wednesday with near-blizzard conditions, stranding commuters, downing trees and alarming residents who had not yet recovered from the first snowfall.

The brunt of the storm hit just as the evening commute was getting underway. The five boroughs and Westchester are on track to get between 7 and 11 inches of snow, and some areas of New Jersey were bracing for as many as 20 inches.

At Pennsylvania Station, commuters trying to return home grew frustrated as trains into New Jersey were canceled or placed on standby. The Port Authority closed its bus terminal in Midtown Manhattan, where strangers pooled their money for an Uber ride into New Jersey. And across the region, the authorities reported hundreds of car crashes as officials cautioned drivers about dangerous conditions and urged them to stay off the roads.

“If you don’t need to be on the road, don’t be on the road,” said Gov. Dannel P. Malloy of Connecticut, who closed state offices at midday. “Just stay home.”