HAVANA — Hurricane Sandy grew into a major potential threat to the Northeast on Thursday after hammering Cuba's second-largest city and taking aim at the Bahamas.
Strengthening rapidly after tearing into Jamaica and crossing the warm Caribbean Sea, Sandy hit southeastern Cuba early on Thursday with 105-mph winds that cut power, damaged homes and blew over trees across the city of Santiago de Cuba.
Cuban officials reported 11 dead from the hurricane, including a 4-month-old baby, NBC News' Mary Murray reported.
The storm weakened to a Category 1, with sustained winds near 90 miles per hour, the National Hurricane Center reported at 11 p.m. ET Thursday night.
The storm has a 90 percent chance of smacking the Northeast and mid-Atlantic early next week with gale-force winds, flooding, heavy rain and maybe even snow, forecasters said Thursday.
"It's going to be a high-impact event," said Bob Oravec, a lead forecaster with the National Weather Service's prediction center. "It has the potential to be a very significant storm with respect to coastal flooding, depending on exactly where it comes in. Power outages are definitely a big threat."PhotoBlog: Hurricane Sandy blows through the Caribbean
The hurricane part of the storm is likely to come ashore somewhere in New Jersey on Tuesday morning, said forecaster Jim Cisco of the NWS prediction center.
"It's almost a weeklong, five-day, six-day event," Cisco added. "It's going to be a widespread serious storm."
It is also likely to hit during a full moon when tides are near their highest, increasing coastal flooding potential.Video: Wide area of Northeast threatened
And with some trees still leafy and the potential for snow, power outages could last to Election Day, some meteorologists fear.
"It could be a Nor'easter on steroids," NWS meteorologist Robert Thompson told NBC station WHDH-TV in Boston. "It’s got the potential to rival the great Nor'easters of the past depending upon the eventual track it takes."
Nor'easters are powerful storms that come up along the East Coast from the south and then increase in volatility with winds from the northeast. In this case, another storm is expected to move into the Northeast from the Ohio Valley around the same time, adding to the weather mix.Interactive: Wild Nor’easters explained (on this page)
Sandy will likely be around for the 21st anniversary of the infamous "Perfect Storm" of Oct. 30, 1991, that killed six fishermen, WHDH noted.
Even before any Northeast impact, eastern Florida as well as the Carolinas and mid-Atlantic states will see high winds, heavy surf and potentially beach flooding, weather.com reported.
New York City Mayor Michael Bloomberg said his staff was "getting out the plans" in case evacuations in flood-prone areas were needed, NBCNewYork.com reported.
'City without trees'
In Cuba, the eye of the Category 2 storm came ashore just west of Santiago de Cuba, the country's second largest city with 500,000 people.
Resident Eduardo Gonzalez said he had walked through much of the city and saw many damaged homes, some almost to the point of complete destruction.
A television reporter described Santiago de Cuba as "a city without trees" after so many were uprooted by Sandy.
Officials gave long lists of towns with damage similar to that in Santiago de Cuba and spoke of the need to provide food, clean water and shelter to residents.
In the city of Guantanamo, east of Santiago de Cuba, television showed telephone poles fallen across narrow streets filled with downed cables. Historic buildings in the city center were damaged, reporters said.
Cuban radio reported that one person had been killed in the storm.
Jamaica was struck earlier by the storm when it was still at Category 1 on the five-step Saffir-Simpson hurricane intensity scale.
One person died in Jamaica, and property was damaged across the eastern side of the island. A person also died in Haiti, where Sandy triggered flash floods.
After Cuba, Sandy was passing over the southern Bahamas Thursday, and then through the nation's central and northwest islands overnight.
The massive Atlantis resort went into lockdown mode after dozens of tourists left Paradise Island before the airport closed. The resort is now less than half full, but all its restaurants, casinos and other facilities are still operating.
Other businesses on Paradise Island, where the capital of Nassau is located, remained closed.
In U.S., worse than 1991 'Perfect Storm'?
For the U.S., the threat keeps increasing for "a major impact in the Northeast, New York area," said James Franklin, chief specialist at the National Hurricane Center. "In fact it would be such a big storm that it would affect all of the Northeast."
Cisco noted the 1991 "Perfect Storm" didn't hit as populated an area and is not comparable to what the East Coast might be facing. Nor is it like last year's Halloween storm, which was merely an early snowstorm in the Northeast.
This has much more mess potential because it is a combination of different storm types that could produce a real whopper of weather problems, meteorologists say.
"The 'Perfect Storm' only did $200 million of damage and I'm thinking a billion," said Jeff Masters, meteorology director of the private service Weather Underground. "Yeah, it will be worse."
Masters was somewhat skeptical on Tuesday, giving the storm scenario just a 40 percent likelihood, but on Wednesday he also upped that to 70 percent. The remaining computer models that previously hadn't shown the merger and mega-storm formation now predict a similar scenario.
The biggest question mark is snow, and that depends on where the remnants of Sandy turn inland. The computer model that has been leading the pack in predicting the system has it hitting around Delaware. But another model has the storm hitting closer to Maine. If it hits Delaware, the chances of snow increase in that region. If it hits farther north, chances for snow in the mid-Atlantic and even up to New York are lessened, Masters said.
Cisco said he could see the equivalent of several inches of snow or rain in the mid-Atlantic, depending on where the storm ends up. In the mountains, snow may be measured in feet instead of inches.
NBC News' Marry Murray, the Associated Press and Reuters contributed to this report.