Gov. Paul LePage declared a statewide emergency Friday to allow state, county and local governments to better respond to approaching Hurricane Irene, and the state’s largest electric utility announced that reinforcements from Canada would be in place even before the storm’s arrival Sunday.

The National Weather Service in Gray followed the declaration by putting the state under a tropical storm watch.

It was still too early Friday night to predict the precise timing or impact of the storm, but it is expected to hit southern Maine sometime late Sunday afternoon or early evening, said meteorologist Dan St. Jean.

“We’re still going with sustained winds of 35 to 50 miles an hour, especially late afternoon or early evening Sunday. Gusts to 60 miles an hour are possible, but that could change,” he said. “We’re not expecting anything stronger than that.”

The track of the storm is still very much up in the air, he said. If it tracks farther inland to the west, the effects of the storm could be quite different in Portland and southern Maine than if it tracks easterly. “A difference of 75 or 100 miles (in its track) will be very noticeable here in Maine,” he said.

Rainfall along the coast is expected to be between 2 and 5 inches. “It won’t be nearly as heavy here as it will be in western New England,” St. Jean said.

LePage’s emergency declaration was accompanied by a statement urging “all Maine citizens to take necessary steps to prepare and heed all warnings issued in connection with this event.”

Central Maine Power took the unusual step of bringing in Canadian line crews to assist. The 60 contract crews will bring the number of line crews to 200, in addition to 150 tree-cutting crews loaned to the utility from within the state, CMP spokesman John Carroll said.

It was only the second time that CMP officials could recall bringing in Canadian crews before a storm in anticipation of widespread damage.

The emergency proclamation allows utility workers to put in extra hours, said Lynnette Miller, Maine Emergency Management Agency spokeswoman.

MEMA and the American Red Cross have been working with local officials to determine where regional shelters may be needed, Miller said. Final decisions on shelter openings will be made closer to Irene’s arrival, she said, though officials in Westbrook and Scarborough announced plans to open their high schools today.

Scarborough High School will open at 3 p.m. while Westbrook High will open at 7 p.m.

Those choosing to use the shelter are reminded to bring essential items, such as a towel, soap, toothpaste, medications and insurance documents. People are also encouraged to eat and shower before they leave their homes.

Irene will cause tens of millions of dollars of lost revenue for the state’s tourism industry as tourists alter their plans or cancel trips altogether, said Charles Colgan, of the University of Southern Maine’s Muskie Institute of Public Service in Portland.

The timing means much of that money will be lost forever because kids are going back to school and it’s too late to reschedule trips this season, he said.

“If this had happened in July, people would’ve postponed their vacations and postponed their travel. But a lot of the losses for tourism won’t be recovered simply because of the timing,” Colgan said, noting that Labor Day, on Sept. 5, marks the traditional end of the summer tourism season in Maine.

Across the state, boatyard workers continued moving as quickly as possible to pull boats out of the water, a factor that could suck even more money from the economy.

At Portland Yacht Services, service manager Rob Benson said about one in 10 boaters told him they’re done for the season and won’t be putting their boats back in the water.

“If your boat is sitting in the parking lot, you’re not putting gas in the tank, you’re not stopping at the local variety store to buy groceries and sandwiches. You’re not coming into the marine store to buy a life jacket. So it’s a (big) impact,” said Rob Soucy, president of Port Harbor Marine in South Portland.

Portland officials today urged residents to prepare for the hurricane by collecting emergency supplies, such as a radio, a flashlight and nonperishable food. Officials also urged residents to bring any outdoor furniture inside their house to prevent it from becoming a projectile.

Mayor Nicholas Mavodones said residents should offer assistance to their elderly neighbors.

“This is a time to reach out and offer a helping hand,” Mavodones said Friday at a news conference at City Hall.

Portland Fire Chief Fred LaMontagne said the highest danger for the harbor and islands will occur Sunday at high tide at 11 p.m.

City officials said they have yet to determine whether to open any shelters, but will announce new developments at a news conference at 10 a.m. today.

People should call 911 for emergencies, Mavodones said, but non-emergency calls should be directed to public services dispatch at 874-8493.

Casco Bay Lines will suspend service to Peaks Island at some point Sunday. The Bailey Island Cruise and Bailey Island Noontime Cruise on Sunday have been canceled.

The National Park Service announced Friday that it will close the Blackwoods and Seawall Campgrounds at Acadia National Park at 10 a.m. Sunday because of the predicted path of Hurricane Irene.

The campgrounds will reopen when the storm has passed.

The opening of the Windsor Fair will not occur Sunday as scheduled. The fair’s board decided to postpone the opening to 1 p.m. Monday to allow the wind and rain to pass and give exhibitors time to set up Monday morning. A new schedule should be available.

The fair, Maine’s second-largest agricultural fair, runs through Labor Day.

Irene will also disrupt the state’s shellfish industry. The Department of Marine Resources announced that after 1 p.m. Sunday, no one will be allowed to harvest clams, quahogs, oysters or mussels from shores, flats and territorial waters along the coast.

The closure is due to pollution anticipated from heavy rainfall and coastal flooding.

While many residents are heading for grocery and hardware stores to stock up, surfers are watching the wave forecast.

Nanci Boutet, owner of Aquaholics in Kennebunk, said she’s not getting too excited just yet. The forecast calls for building surf throughout the weekend. Seas around 2 feet today will build to 5 feet by Saturday night and up to 15 feet Sunday afternoon. As the storm leaves Monday, waves will subside to about 6 to 8 feet by afternoon and that’s what Boutet is looking forward to.

“Monday afternoon is probably going to be beautiful and the lifeguards are not going to be impressed,” with all the surfers enjoying the waves, she said.

Hurricane season does limit her shop’s rental business, however. She said the store likely won’t rent surfboards to beginner or even moderately experienced surfers.

“If they’re not a seasoned veteran surfer and there is any question in their mind whether they can handle it, they should just watch,” Boutet said.