New York (CNN) -- New York City, that land of hustle and bustle, took on a new character Saturday: Quietness, punctuated by bursts of activity.
The imminent approach of Hurricane Irene made for some mighty unusual scenes.
Long lines were common at grocery stores as residents stocked up, but streets appeared empty just a couple blocks away.
"Once you get outside major hotel areas it gets quiet pretty quickly," said Dan Pinter, a sales associate at New York Running Company, an athletic shop near Central Park in Manhattan.
Under siege from natural forces and under a tornado watch late Saturday, the city was going without its subway system, incoming flights and other transportation services. Mayor Michael Bloomberg had issued a mandatory evacuation order for more than 370,000 residents of low-lying areas in the city. Thousands of public housing residents on the Lower East Side were being taken by bus to shelters.
CNN iReporter Jon Michael Gimpel, 42, a resident of the Upper West Side, took photos of closed businesses and buildings. He likened the emptiness of the streets to the eerie aftermath of September 11, 2001.
"We got cabin fever and walked around," said Gimpel, a system engineer. "A lot of shops are closed. No one knows what to do."
Besides telling people to heed evacuations and to stay away from windows, Bloomberg asked residents to stop being a little too helpful.
Saturday morning, city crews turned over trash baskets, trying to make them less likely to cartwheel away when anticipated strong winds arrive Sunday. Some citizens turned them rightside up.
CNN iReporter Elie Shaby submitted a photo of sandbags in front of the Apple Store on West 14th Street, which planned to reopen Monday.
Shaby said the mandatory evaluation ends at 41st Street, one block away from where she lives. She does not plan to evacuate but said, "living in New York City all my life and never experiencing a hurricane before, I have no idea what to expect."
Eden Pontz, executive producer at CNN's New York bureau, said only two riders were on her subway car as she rode from Brooklyn to work at Columbus Circle in Manhattan.
Cabbies scoured neighborhoods for evacuees and other riders. Tourists were still evident in many parts of the city.
Gimpel saw several eating from the bar stools at an Irish pub. Normally, they would be dining in Manhattan's restaurants, he said.
Irene, a Category 1 hurricane with top sustained winds of 80 miles per hour, was heading into Virginia later in the day, taking aim for the Norfolk area. It will pound the Delmarva Peninsula overnight and hit the New Jersey coast early Sunday, with Philadelphia and New York City in its sights.
The massive Metropolitan Transportation Authority was shut down at noon. The system, which provides 24-hour subway and bus service across the city, is the transit lifeblood of New York. Its buses, subways and railroads carry about 5 million riders daily. And it might not be fully back up by Monday, Bloomberg said.
At the Seventh Avenue station in Brooklyn's Park Slope section, more than a dozen people waited for one of the final subway runs. "What I'm hoping is that they will run trains for the next hour or two to pick up the stragglers," Kate Sandberg, who was headed to visit a friend, told CNN affiliate WABC.
Saturday, Bloomberg exhorted residents to leave immediately.
"Let's stop thinking this is something that we can play with. Staying behind is dangerous, staying behind is foolish, and it's against the law. And we urge everybody in the evacuation zone not to wait until there are gale force winds and driving rain to leave," Bloomberg said.
Pinter, 25, said the running store kept busy Saturday, but he expects it to be much quieter Sunday -- if it remains open.
He lives about 50 blocks away and said he is prepared to jog home if he can't get a cab.
"We'll take it as it comes," he said of Irene. "I say there is more curiosity than concern."
The evacuation zone included Battery Park City on the southwestern tip of Manhattan.
"It's very quiet," said state Sen. Daniel Squadron, whose district includes the community. "There are few people out who do not have large shopping bags."
CNN's Phil Gast, Eden Pontz and Chris Boyette contributed to this report.