(CNN) -- States along the East Coast were pummeled by post-tropical storm Sandy on Monday as it came crashing ashore.
The storm officially made landfall along the coast of southern New Jersey, but it is affecting a much wider area.
By Monday night, more than 2.8 million customers were without power across 11 states and the District of Columbia, according to the latest CNN estimate. At least 11 people have died.
Here's a look at how coastal states are dealing with the storm:
One person was killed and two sustained injuries that weren't life-threatening after a large tree fell on them in Mansfield, according to a statement from Connecticut State Police.
Gov. Dan Malloy said authorities are worried about high tides, particularly the one at midnight Monday, which could be up to 11 feet above the normal high tide and "has the potential to cause unprecedented damage."
"The potential loss of life and loss of property in Connecticut, if these numbers are hit, will be extremely high," he said. "This is the most catastrophic event that we have faced and been able to plan for in any of our lifetimes. And we continue to do anything in our power to be ready."
Because of dangerous driving conditions, all state highways were closed to nonemergency vehicles starting at 1 p.m. Monday, the governor said in a statement.
President Barack Obama has declared a state of emergency for Connecticut.
Parts of the Delaware coast experienced significant flooding.
By early Monday, the National Guard and local authorities were responding to residents who did not evacuate and "need to be rescued from flooding," Gov. Jack Markell said in a Twitter post.
Markell ordered the evacuation of all coastal communities and a flood-prone area in southern Delaware.
Shelters opened beginning Sunday afternoon to accommodate those who have left their homes but have nowhere else to go. Statewide, 500 people spent the night in five shelters, Markell said Monday.
"The biggest concerns, the rain and the wind together make driving conditions absolutely miserable, so we put in a driving restriction today," he said.
The restrictions mean only "essential personnel," such as core government employees and those who provide health care services, should be driving.
Obama declared a state of emergency in the state Monday, the White House said.
DISTRICT OF COLUMBIA
The city's mass transit system, known as the Metro, stayed idle Monday.
All Washington public schools were closed Monday, Mayor Vincent Gray announced. The district readied for the storm's effects, which could include heavy rain, street flooding, strong winds, power outages and storm-surge flooding along the Potomac River and its tributaries, Gray said.
All federal buildings were closed to the public Monday and will be Tuesday as well.
President Barack Obama declared a state of emergency in the District of Columbia on Sunday.
The Maine Emergency Management Agency warned Sandy could create "significant problems" such as high surf, fierce winds and coastal erosion.
Flooding is also possible in areas where rain is heaviest, emergency officials said.
In anticipation of widespread power outages, Gov. Paul LePage signed a "limited emergency declaration" so power crews from other states and Canada can help the state prepare for Sandy. The declaration also extends the hours that power company crews can drive.
Gov. Martin O'Malley said officials in Maryland prepared for the worst.
"This is going to be a long night," he said late Monday. "We're only now just kind of beginning the rough part of this storm. These next 12 hours will likely be the most intense."
Public schools in Baltimore, Montgomery and Prince George's County were closed Monday. Baltimore Mayor Stephanie Rawlings-Blake announced mandatory travel restrictions for city roadways, starting at 6 p.m. Monday.
In the coastal city of Annapolis, city crews distributed sandbags to residents and businesses to help them prepare for flooding.
Obama declared a state of emergency in Maryland on Sunday.
Gov. Deval Patrick declared a state of emergency for the Bay State.
Hoping to avoid the kind of criticism utilities received after last year's Hurricane Irene and other storms, Patrick said utilities plan to pair tree removal and power restoration crews, rather than having them work separately, so that work can be done more efficiently.
Boston announced that schools were closed Monday, and all public transportation services in the city were suspended. Schools were scheduled to be open Tuesday.
Obama also declared a state of emergency for Massachusetts.
"All in all, we're holding our own," Patrick told reporters Monday afternoon. "I think it's going well, but it's nature, and it can change in a minute."
Sandy could bring winds of up to 70 mph and dump 1 to 4 inches of rain to parts of the Granite State, Gov. John Lynch's office said.
Lynch urged drivers to stay off the state's roads and asked employers to release workers early Monday afternoon to avoid travel after 3 p.m. when high winds and heavy rains were expected to intensify.
"This will be significant storm for New Hampshire, and we are urging all citizens to exercise common sense and extreme caution," Lynch said in a statement after declaring a state of emergency.
The governor asked the National Guard to place 100 troops on active duty, with 100 more on standby.
Two people in Morris County were killed Monday evening when a tree fell on their car, authorities said. A male of unknown age was also killed in Hawthorne when a tree fell on a house, according to Hawthorne Fire Chief Joseph Speranza.
Several feet of water were flooding parts of Atlantic City on Monday, and authorities worked to evacuate hundreds of people from West Atlantic City, where waters were "dangerously high," said Linda Gilmore, a spokeswoman for Atlantic County.
Atlantic City was under curfew from 6 p.m. Monday until 6 a.m. Tuesday.
"When Mother Nature sends her wrath your way, we're at her mercy, and so all we can do is stay prayerful and do the best that we can," Atlantic City Mayor Lorenzo Langford told CNN.
He said the city could get as much of 5 feet of water, and video showed downtown streets looking like rivers.
New Jersey was the first to announce mandatory evacuations. The state's barrier islands from Sandy Hook south to Cape May were ordered to clear out, along with Atlantic City's casinos.
"We're at a moment now where evacuations are no longer possible. And we're no longer able to come and rescue people," Gov. Chris Christie said Monday afternoon.
Addressing those who chose not to evacuate, he said: "We will not be able to come and help you until daylight tomorrow. Please try to hunker down and stay safe until then."
All state offices were closed Monday, with only essential employees expected to report to work, Christie announced. The same will be true Tuesday.
New Jersey Transit came to a halt and will remain suspended indefinitely. Flooding from Sandy also forced the closure of Newark Liberty International and Teterboro airports.
Obama declared a state of emergency in New Jersey, Christie announced Monday.
"We knew that this was going to be a very dangerous storm, and the storm has met our expectations. The worst of the weather has come, and city certainly is feeling the impacts," New York City Mayor Michael Bloomberg said late Monday.
Hundreds of thousands of New Yorkers were without power. A slow surge of water flooded parts of Lower Manhattan, and downed trees littered the city, sparking fires, the mayor said.
"These are not games. We've said from the very beginning, this is a once in a longtime storm," he said.
At least five people were killed in New York because of Sandy, said Rich Azzopardi, a spokesman for New York Gov. Andrew Cuomo. One of the victims died when a tree fell on his home in Queens.
New York City's ubiquitous public transit system shut down ahead of Sandy's landfall, leaving iconic sites such as Grand Central Terminal and Penn Station empty.
Flooding was confirmed inside subway stations in Lower Manhattan, MTA spokesman Kevin Ortiz said late Monday. As for possible damage, "It's too early to tell," he said.
Energy company Con Edison shut off power to parts of Lower Manhattan and Brooklyn. Seawater from the storm surge threatened to flood the underground system.
Flooding also forced the closure of two major airports, John F. Kennedy and LaGuardia. The runway intersection at the latter was covered by water.
Mandatory evacuations are in place for parts of the city. Evacuation centers have been opened in 76 locations, and schools were closed Monday.
Offices at the United Nations in Manhattan also were closed Monday. So was the New York Stock Exchange, which officials said would also be closed on Tuesday.
The Broadway League canceled all Broadway performances Monday and Tuesday night. Instead of tourists and theater fans, piles of sandbags lined Broadway.
Meanwhile, a crane atop a luxury Manhattan skyscraper under construction partly collapsed Monday, leaving its arm precariously perched and hanging over West 57th Street. New York City is experiencing strong winds because of Sandy, and the property group managing the site blamed the collapse on the storm.
Ahead of possible flooding, New York officials closed various bridges and tunnels, including two key traffic arteries Monday: the Hugh L. Carey and Holland tunnels, which connect Manhattan with Brooklyn and Jersey City, New Jersey, respectively. They also announced the closure of the Tappan Zee Bridge, which stretches across the Hudson River about 25 miles north of New York City.
Gov. Cuomo directed 2,000 troops to mobilize for Sandy, and Obama has declared a state of emergency for New York.
Crew members of a tall ship used for classic adventure films faced a harrowing real-life drama Monday as Hurricane Sandy forced them to abandon ship about 90 miles off Cape Hatteras, North Carolina.
Fighting waves towering 18 feet high and winds of 40 mph, a group from the HMS Bounty boarded two lifeboats, the Coast Guard said. Two helicopter crews saved 14 people stranded in the Atlantic Ocean.
A deckhand missing from the ship was found dead, the Coast Guard said. The ship's captain remains missing.
Strong winds and rain that fell sideways lashed the Outer Banks as the outskirts of Sandy pummeled the barrier islands.
Forecast expect between 4 and 7 inches of rain to fall over several days in the Outer Banks, with some spots receiving eight or more inches.
North Carolina Gov. Beverly Perdue has declared a state of emergency for 24 counties in the western part of her state due to snow.
Gov. Tom Corbett declared a statewide disaster emergency ahead of the storm.
Flooding, power outages and sustained high winds are anticipated, his office said. Sandy could even bring snow to parts of southwestern Pennsylvania and in higher elevations.
"Essentially, this is a hurricane wrapped in a nor'easter," Corbett said.
Throughout the state, 1,600 National Guard troops were deployed, the governor said in a Twitter post.
Public schools in Philadelphia were closed Monday. Public transportation in the Philadelphia area has also been suspended.
The Rhode Island Emergency Management Agency urged all residents to prepare for prolonged power outages, wind damage and water damage by keeping an emergency kit, securing property and taking boats out of the water.
State authorities have taken precautions such as checking and clearing drains in flood-prone areas and relocating state equipment if necessary.
Public schools in Providence, the state capital, were closed Monday.
Obama has declared a state of emergency for Rhode Island.
Heavy rains from the fringes of Sandy pelted much of South Carolina's coast, from Charleston to Myrtle Beach.
Virginia was one of several states to declare a state of emergency ahead of the storm. Computer models predict parts of the state could see as much as a foot of rain.
Gov. Bob McDonnell said Monday morning that his state had seen signs of the storm for days, but the worst was yet to come. He asked for a federal emergency declaration, which would free up funding.
Sandbags piled up inside restaurants in the Old Town section of Alexandria along the banks of the Potomac River.
All public schools in Fairfax County, a large school district in northern Virginia, will be closed Monday and Tuesday. Schools in Arlington, Norfolk and Newport were closed Monday.
A woman was killed in a car accident after the storm dumped 5 inches of snow on the town of Davis, said Amy Shuler Goodwin, a spokeswoman for Gov. Earl Ray Tomblin's office.
West Virginia has declared a state of emergency as Sandy is dumping heavy snow and rain in parts of the Appalachian Mountains.
CNN's Soledad O'Brien, Suzanne Malveaux, Mark Norman, Jason Kessler, George Howell and Athena Jones contributed to this report.