Hurricane Sandy has weakened with maximum sustained winds of 75 mph as of 2 p.m., but it is still expected to be a massive and powerful system for the next several days that could strike the Delmarva peninsula at hurricane strength and cause hundreds of thousands of power outages in Maryland.
The storm's center is expected to strike the Delmarva early Tuesday before moving to the northwest over Baltimore, according to the National Hurricane Center's 5 p.m. update.
Gov. Martin O'Malley declared a state of emergency Friday morning launching statewide storm preparation efforts led by the Maryland Emergency Management agency. Mayor Stephanie Rawlings-Blake also launched readiness efforts Friday, coordination with state officials.
"As Hurricane Sandy makes its way north, I urge all Maryland residents to prepare for extreme weather," O'Malley said in a statement. "I urge all Marylanders to review their family emergency plans, make sure their emergency supplies like batteries and water are fully stocked and to stay informed."
A tropical storm watch is in effect for the Carolinas, and more watches could be extended up the coast Friday. The storm was about 400 miles southeast of Charleston, S.C., as of 2 p.m.
While the storm has weakened slightly since Thursday, heavy and damaging winds still extend far out from the center of the storm, according to the hurricane center. Hurricane-force winds of at least 74 mph extend 35 miles out from the center, and tropical storm force winds of 39 mph to 73 mph extend out 275 miles from the center.
If that strength and the forecast track hold up, it would mean tropical storm force winds could start affecting Maryland on Monday. Some rain and breezy winds could start late Sunday, with rain and heavy winds throughout Monday and Tuesday, according to forecasts.
Still, other forecast models were showing Sandy making landfall to the north in New Jersey or Long Island and then circling back inland to affect Maryland later, on Tuesday.
Foot's Forecast is warning of possible tropical storm force winds up to 150 miles inland from North Carolina to New Jersey and New York City, with 6 to 12 inches of rain possible across parts of half a dozen states. "Extreme" coastal flooding and severe beach erosion are possible with 10-20 foot waves pounding over a period of two days.
NASA satellite images show the storm grew by 120 miles in diameter overnight, to about 410 miles wide.
In Baltimore City, Mayor Stephanie Rawlings-Blake convened a meeting of city agency heads and others on Friday to go over plans for responding to Hurricane Sandy.
According to city officials, the Mayor’s Office of Emergency Management will be fully staffed starting at 7 a.m. Sunday and from then on to respond to the storm.
Robert Maloney, the deputy chief of emergency management and public safety for the city, said city emergency workers need to do all they can to prepare for the storm.
"We're in a very serious situation," he said. "Everyone thought the hurricane season was over, but it’s not over."
Maloney said he expected the city's response efforts to continue until the end of next week, whether that means clearing downed trees or pumping out flooded basements or something else.
"There's no good-case scenario, because you don’t know what poison pill you want," he said. "If this storm goes on its projected path, we're going to be doing something until next Friday."
Weather watchers continue to debate models' predictions for Sandy's track and are already expecting it to be a historic storm for much of the country.
Many are predicting record-low pressure measurements when the storm arrives -- potentially as low as 930 millibars, according to local meteorologist Eric the Red. That is the equivalent of 27.5 inches mercury on a home barometer. For comparison, according to Eric, the superstorm of March 1993 had pressure of 960 millibars, or 28.3 inches mercury.
According to atmospheric scientists at the National Center for Atmospheric Research, a hook in Sandy's track -- in which the storm is expected to swing out to sea somewhat before turning back and striking the coast head-on -- would also be unprecedented and devastating.
Of the hurricanes at least category 2 strength that have passed up the East Coast toward New York since 1850, none have made such a hook, according to an article NCAR's Bob Henson posted Thursday. The unusual head-on hit could bring massive storm surges and coastal flooding because of the storm's forward movement directly into the coast. A full moon could also worsen the flooding.
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Sun reporter Edward Gunts contributed to this report.