Hurricane Irene
President Barack Obama is directing the U.S. Government response to Hurricane Irene, in conjunction with state and local officials. The storm poses perhaps the biggest natural threat to the region since the repeated blizzards that affected the Mid-Atlantic / Northeast regions during the winter of 2009-2010. REUTERS

As Hurricane Irene prepared to make uninvited ports-of-call to Washington, Baltimore, Philadelphia and New York, President Barack Obama warned Saturday that the United States' East Coast was in for a long 72 hours as he led the U.S. Government's response from a disaster command center in Washington.

Obama chaired a meeting at the National Response Coordination Center (NRCC) set up at the Federal Emergency Management Agency's (FEMA) headquarters in Washington, which is coordinating and marshaling federal and local hurricane-relief efforts.

Storm: Mini-Marathon for All

This is going to be a tough slog getting through this thing, Obama said during a video teleconference including senior federal officials and local government agencies in the east coast path of Irene, Agence-France Presse reported Saturday.

Obama added that the storm would put an enormous strain on a lot of states that could last days, or even longer, in some locales. The biggest concern I'm having right now is due to flooding and power, he added.

Obama and other NRCC officials then heard updates from governors and emergency management officials in North Carolina, Virginia, Maryland, Delaware, Pennsylvania, New Jersey, New York, Puerto Rico, Connecticut, Rhode Island, New Hampshire, Maine and Vermont.

The president took over the federal government's response Friday, returning early from his vacation, and met and spoke with U.S. Homeland Security Secretary Janet Napolitano, FEMA Administrator Craig Fugate, and other senior management officials, ABCNews.com reported Saturday.

Concerning Irene's position, as of 5 p.m. EDT, Irene, a Category 1 hurricane, was straddling the North Carolina/Virginia border with winds up to 80 miles per hour (mph), moving north/north east at about 13 miles per hour, according to weather.com.

Irene did make land-fall in the Carolinas, near Cape Lookout, N.C. at about 8 a.m. EDT, but meteorologists say that can be deceptive: hurricanes frequently touch land, then skirt the coast, before moving back out on to the sea, where they re-strengthen. In other words, Irene could re-strengthen in the days ahead -- creating even more damaging winds, storm surge, and rain.

Forecasters expect Hurricane Irene to reach New Jersey by Sunday at 1 a.m. EDT, then New York City by 6 p.m. EDT, then likely be downgraded to a tropical storm as the storm center passes over Fairfield County, Conn. later Sunday. Rain amounts of 4 to 8 inches and higher, with damaging winds are expected throughout the Northeast Coast, and some areas could receive over 12 inches of rain.

Major Transportation Systems, NYC Subway Shut Down

U.S. airline, rail and transit systems in New York and other eastern cities initiated sweeping weekend shutdowns and slowdowns on Saturday as Hurricane Irene bore down on the region.

Tens of millions of air travelers, train passengers and subway and bus riders scrambled to adjust their routines, work commutes and vacations as transportation networks gradually scale back operations to minimize disruptions, Reuters reported Saturday.

Coordinated transportation-related closures or slowdowns, often seen during winter storms in the Northeast, were mostly announced on Friday to give travelers enough time to adjust and ensure they stay away from Irene's fury.

New York's subway system, which carries 7 million riders daily and operates the largest fleet in the world, had never closed due to weather: city officials shut down the system Saturday. The storied Staten Island Ferry was to suspend service Saturday night