Hurricane Irene from New England Perspective

A satellite image taken at 5:45 p.m. yesterday showed Hurricane Irene as it moved northward along the East Coast. Rain from the storm should arrive late tonight. (National Oceanic and Atmospheric Administration)

Governor Deval Patrick declared a state of emergency yesterday and called up 2,500 members of the National Guard ahead of Hurricane Irene, an enormous storm expected to plow into New England packing a triple threat of high winds, heavy rain, and surging seas.

The rain should arrive first, beginning late tonight. By early tomorrow afternoon, Irene’s winds are forecast to pick up and could exceed 50 miles per hour for as long as 10 hours, with gusts above 70.

The storm is expected to spin across Massachusetts, threatening everything to the west of the eye with drenching rain, while regions to the east will be subject to the highest winds.

“We expect this to be a powerful and potentially dangerous storm,’’ Patrick said.

The hurricane has already caused cancellations of everything from airplane flights to long-planned weddings, and disrupted the daily routines of millions of people.

New York City is undertaking its first mandatory evacuation today, clearing some 250,000 people from low-lying waterfront areas and taking the extraordinary step of shuttering its subway system during the storm.

In New Hampshire, the US Forest Service is closing the White Mountain National Forest to visitors.

President Obama cut short his Martha’s Vineyard vacation and returned to Washington last night.

Although some forecasters were predicting the storm would lose power as it reached New England, no one can yet say for certain what kind of punch Irene will deliver. Will it resemble Hurricane Gloria in 1985, a colossus that followed a similar track, but faded as it landed in New England and left little damage? Or Hurricane Carol, which raced up the coast in 1954, smashing homes, submerging cars in downtown Providence, and ripping the steeple off the Old North Church?

A storm’s path, size, forward speed, and intensity all contribute to its destructive power, said Jay Barnes, an author and hurricane historian from North Carolina.

“No two hurricanes are alike, and they each have their own brand,’’ he said.

The benchmark for destructive New England storms is the Hurricane of 1938, a nightmare in the childhood memories of many of today’s great-grandparents.

“That was an unusual storm, which raced north with rapidly accelerating forward speed,’’ which gave it tremendous power, said Barnes. “Right now, it seems Irene is not going be one of those kinds of storms.’’

Irene is so far a slowpoke, chugging along at 14 m.p.h. or so. Unless it dramatically changes, “The rains and the wind are going to start early and stay late,’’ Barnes said.

Irene could come close to rivaling Bob, the 1991 storm that killed six in Southern New England and wreaked hundreds of millions of dollars in damage, said Bill Simpson, a meteorologist at the National Weather Service in Taunton.

Most New Englanders have lived through hurricane warnings and know the drill: Get the boat out of the water, haul the patio furniture to the basement, and load up on batteries.

But some, like the state’s apple growers, are at Irene’s mercy, and the timing could not be more perilous: Trees are heavy with ripening McIntosh apples, a classic New England variety, not quite ready to be picked. A wallop from Irene could devastate this year’s harvest.

“We just pray and keep our fingers crossed and hope for the best,’’ said Julie Martin-Sullivan, a third-generation owner of Honey-Pot Hill Orchards in Stow.

Irene is a sprawling storm, and state emergency officials expect the effects will stretch across Massachusetts.

Kurt Schwartz, executive director of the Massachusetts Emergency Management Agency, said authorities are planning for significant flooding on the west side of the storm, high winds on the east, and a strong storm surge on south-facing coastal areas. The timing of Irene’s lumbering arrival will be key to the size of the storm surge – whether it arrives as the tide is coming in or out will determine how far water is shoved on shore.

Logan International Airport is scheduled to stay open during the storm, though it is doubtful anybody will be flying. About 80 percent of Sunday flights had been canceled yesterday.

No service interruptions are expected for trains and buses, officials said. But all state parks will close to camping at noon today and will remain off-limits until Tuesday. State beaches, particularly those on the Southeast coast, are also closing.

In Plymouth yesterday, Jeff and Linda Watt of Sioux City, Iowa, were among the few tourists outside enjoying the last bits of calm before Irene.

“We just got chased out of Iowa by tornadoes,’’ said Jeff Watt. “Now we come out here and there are earthquakes and hurricanes. Give me a break.’’

Plymouth hotels and restaurants were wrestling with contingency plans. The front desk of the Radisson was stocked with flashlights and glow sticks, and the restaurant had bought cold-cut platters to feed guests in the event of a power outage. Across the street, the East Bay Grille was trying to move an outdoor wedding scheduled for tomorrow indoors to another facility. “We’re just waiting on the word from the bride,’’ said general manager Erik Daigle.

At historic Old North Church in the North End, which has twice lost its steeple to hurricanes, Pam Bennett, retail manager for the Old North Foundation, said the vicar would likely cancel Sunday’s service and close the church for the day. The historic site will be open for tours today but will probably close early, Bennett said. Workers will cover some “precarious’’ windows with plywood and apply tarps to protect other spots that could be damaged by water or wind.

At National Grid’s New England Distribution Center in Whitinsville, staff have been preparing for Irene by distributing supplies to utility staging sites around the state: transformers, cables, fuses. Everything necessary to fix an outage, or repair a downed line or pole, comes from this warehouse.

“We basically pre-stage these materials at our crew sites,’’ said Daniel Prior, manager of warehouse operations in New England, as he walked among thousands of transformers and hundreds of reels of cable. “They’re going to get enough that they can work independently for one to two days.’’

Hospitals around the state have been working for days to make sure their generators are fueled, their linens and medications are fully stocked, and their kitchens prepared.

Emergency professionals used to assume that stocking hospitals with two to three days’ of supplies was enough to prepare for a weather emergency. Hurricane Katrina taught them otherwise, said Gina M. Smith, a nurse and emergency preparedness coordinator at UMass Memorial Medical Center. Now the hospital prepares for at least four days.

“That’s what’s ideal about a hurricane – if you pay attention to the warnings you’re given, you do have time to make some preparedness efforts,’’ Smith said.

Across the city yesterday, many Bostonians seemed ready to hunker down. Some were rushing to the supermarket and hardware stores. Others displayed a cool sense of heard-it-all-before.

Yudy Juilian of the South End was at the Save-A-Lot in Roxbury to stock up on food for herself and her two children. Originally from the Dominican Republic, Juilian said she’s taking the threat of a storm seriously.

“After 14 years of living here, they’ve never announced that a hurricane is coming to Boston,’’ she said. “It’s just better to be safe than sorry.’’

In the South End, some men were enjoying a gorgeous Friday afternoon, lazing about in fold-up chairs and smoking cigarettes. Hiran Rondan, whose home is already stocked with water, food, and flashlights, gazed at his neighbors’ outdoor tent – decorated with Christmas lights -and mused about whether they planned to take it down.

“It might just be in pieces when it’s all over,’’ he said.

Mark Snider, manager of the Winnetu Oceanside Resort in Edgartown, said he wasn’t too worried. The hotel, with a capacity of 700, was full. “There’s actually kind of a festive feeling,’’ he said. “We’ll have a special storm buffet at the restaurant. We’ll move the yoga class indoors. And we’ll show movies in our theater.’’

Not among those movies, though: “The Perfect Storm.’’

Erin Ailworth. Mary Carmichael, Chelsea Conaboy, Martin Finucane, Meghan E. Irons, and Akilah Johnson of the Globe staff and Globe correspondent Neena Satija contributed to this report. Mark Arsenault can be reached at [email protected]