New Jersey's famously blunt Gov. Chris Christie was less polite: "Don't be stupid. Get out."
New York called off school Monday for the city's 1.1 million students and announced it would suspend all train, bus and subway service Sunday night. More than 5 million riders a day depend on the transit system.
The New York Stock Exchange announced it will shut down its trading floor Monday but continue to trade electronically.
Officials also postponed Monday's reopening of the Statue of Liberty, which had been closed for a year for $30 million in renovations.
In Washington, President Barack Obama promised the government would "respond big and respond fast" after the storm hits.
"My message to the governors as well as to the mayors is anything they need, we will be there, and we will cut through red tape. We are not going to get bogged down with a lot of rules," he said.
He also pleaded for neighborliness: "In times like this, one of the things that Americans do is we pull together and we help out one another And so, there may be elderly populations in your area. Check on your neighbor, check on your friend. Make sure that they are prepared. If we do, then we're going to get through this storm just fine."
The storm forced the president and Mitt Romney to rearrange their campaign schedules in the crucial closing days of the presidential race. And early voting on Monday in Maryland was canceled.
Despite the dire warnings, some souls were refusing to budge.
Jonas Clark of Manchester Township, N.J. â¿¿ right in the area where Sandy was projected to come ashore â¿¿ stood outside a convenience store, calmly sipping a coffee and wondering why people were working themselves "into a tizzy."
"I've seen a lot of major storms in my time, and there's nothing you can do but take reasonable precautions and ride out things the best you can," said Clark, 73. "Nature's going to what it's going to do. It's great that there's so much information out there about what you can do to protect yourself and your home, but it all boils down basically to 'use your common sense.'"