Ignoring the calendar, which showed the beginning of the month of July, a dusting of snow fell Thursday on Mount Washington in New Hampshire, startling tourists and forcing the closure of the road to the top.

"It's not extraordinary, but it's definitely interesting," said Stacey Kawecki, a meteorologist for the Mount Washington Observatory.

Mount Washington, the Northeast’s highest peak at 6,288 feet, has recorded snow in every month. The last time it was recorded in July was 2007.

The snow fell from about 8:30 a.m. to 9 a.m. and then from 10 a.m. to noon, Kawecki said.

It was "about 35 degrees and there was a thick and soupy fog. Visibility was about 100 feet and ice was starting to form on the windows. Then I saw big, fat, floppy flakes hitting the windows," Kawecki said.

The sand-colored shorebird had all but disappeared by the 1980s along the East Coast, as the beaches it nests on were developed and visited more often by people.

Efforts to save it by restricting vehicles on beaches sparked a backlash — there was even a Facebook page called “I Hate the Piping Plover.’’

Now, the oil spill in the Gulf of Mexico appears to be the tiny white bird’s latest nemesis.

Plovers are beginning to fly south as part of an annual migration to gulf shores now fouled with oil. Two weeks ago, bird specialists found the season’s first two piping plovers on the remote Chandeleur Islands off Louisiana, where oil has already washed up. More birds will arrive in the next month and stay on gulf beaches through the winter.

“We are very worried,’’ said Scott Hecker, a coastal water bird specialist and executive director of the Massachusetts-based Goldenrod Foundation, which works to protect barrier beaches. “These remote beaches along the gulf are where the birds go, and they are the places that get the oil first and the most.’’

The bird is the latest in a series of New England species — bluefin tuna and sea turtles are others — whose populations may suffer because they spend part of their life in the gulf.

Unlike seabirds that spend most of their time in the water, piping plovers prefer the shore and are best known for their short bursts of running in the flat, muddy area between the high tide mark and the water line. Specialists fear some may become coated in oil that washes ashore, but they are also concerned the birds’ food source — tiny worms and other marine life — may become polluted and, in turn, poison the birds.

Once, piping plovers were common along the Atlantic Coast, but they were heavily hunted — along with other shorebirds — for their feathers, used in hats. Protected in 1918 by the Migratory Bird Treaty Act, the birds’ populations rose through the 1940s, but after World War II began declining again, in part because development ate up areas where they nested.