The wild horses do not exist where the movie takes place. They are actually about 60 miles north near Corolla. They would have to swim across a wide inlet to get to Rodanthe from Corolla. Another herd of these wild horses is on Ocracoke Island, about 35 miles south, but are penned in for their protection. Another herd of these wild horses are located on the Cape Lookout National Seashore, and freely roam between Cape Lookout, Shackleford Banks, and Carrot Island, near Beaufort, NC.
Early in the film, right after he checks in and she is in the kitchen to prepare dinner, she finds a photo on the refrigerator of her and her family, including her separated husband, and moves it to a cabinet. In the next shot she is working on dinner with the cabinet behind her and the photo is not there.
In the beginning of the film, when Dr. Paul Flanner is driving to Rodanthe, there is a short scene in which he's driving on US-17 south of Myrtle Beach, SC. (The store with the big sharks mouth entrance) This is nowhere near his supposed driving route. The store with the giant shark is actually the Shark Attack Souvenir and Gift Shop at 1295 NC Highway 210, Sneads Ferry, NC.
In the opening sequence Dr. Paul Flanner is shown driving north on Route 12, apparently toward Rodanthe from Raleigh. (The ocean is to his right.) And he's seen making a ferry crossing, later discussed in the dialogue, which would have been the Ocracoke-Hatteras Island ferry, south of Rodanthe. But in the same early sequence, he's seen crossing the Herbert C. Bonner bridge at Oregon Inlet, which is actually north of Rodanthe, connecting Bodie Island and Hatteras Island. In fact, the driving route between Raleigh and Rodanthe would almost certainly not include any ferry crossings, which are considerably further south than the Raleigh-Rodanthe route, and would approach Rodanthe from the north.
Before the hurricane made landfall, Adrienne said that the US Coast guard issued a hurricane warning for their area of the North Carolina coast. The US Coast guard cannot issue weather related warnings. It would have been the National Hurricane center that issued the warning.