Empty except for the barkeeper, who was preparing the bar car for the commuter rush.

"It will be done long before or long after the commuter rush," Mr. Lhota said.

Mr. Kelly acknowledged that traffic, which sometimes seems to calcify during a normal commuter rush, would present a significant challenge.

"We're in the commuter rush," he said.

"We worked very hard to establish the commuter rush."

During the commuter rush, trains roar through Harold Interlocking at the rate of 42 an hour.

During the commuter rush, as many as 4,600 vehicles pass through the intersection every hour, according to the city's Department of Transportation.

Not surprisingly, exposure to outdoor ads peaked during the commuter rush.

There was a signal failure at the height of the commuter rush on Monday morning, which backed up 27 trains.

They returned to Defiant in the early evening-during the shift-break commuter rush.