Consuello Jessop, of Providence, R.I., photographs the sunrise at Ocean Park, Thursday, July 12, 2018, in Old Orchard Beach, Maine. Sunny skies, warm air and low ocean temperatures expected this weekend have prompted the National Weather Service to issue a warning to beachgoers to beware of hypothermia. Credit: Robert F. Bukaty | AP

The National Weather Service is warning beachgoers to beware Maine’s deceptively cold and potentially deadly coastal waters this weekend.

The weather service’s beach hazard warning to Hancock and Washington counties issued Friday includes Bar Harbor, Bucksport, Castine, Cherryfield, Eastport, Ellsworth and Machias. It lapses Sunday, said Priscilla Farrar, a meteorologist with the NWS office in Caribou.

Friday’s warning — the 18th issued this year — comes with flocks of tourists visiting Maine. Many, Farrar said, are likely unfamiliar with how the seasonal air temperatures in the upper 70s can mask cold water temperatures in the low 50s that can cause hypothermia, a medical emergency that occurs when body temperatures, which typically run about 98.6 degrees Fahrenheit, fall below 95 degrees.

[Hypothermia: Its causes and treatments]

“It will be a nice weekend and we don’t want people to be surprised by the cold waters,” Farrar said Friday.

The remnants of Tropical Storm Chris might also create additional hazards by creating heavy currents along the Gulf of Maine as it heads away from the east coast, according to a warning issued by the Hancock County Emergency Management Agency.

The weather service has worked with state emergency management agencies to issue warnings to underline the hazards posed by Maine’s waters since April, Farrar said.

Hypothermia can occur gradually from immersion in waters colder than 60 degrees. Its symptoms include shivering, slurred speech, slowed breathing, lack of coordination and drowsiness, according to the Mayo Clinic website.

[The beach hazards warning from the National Weather Service for Hancock County]

The weather service warns visitors, particularly to Acadia National Park, Schoodic Point, Lamoine State Park, Castine Roque Bluffs State Park and Quoddy Head State Park, to be watchful.

Coastal water temperatures south of Hancock County are expected to be warm enough to make hypothermia less likely, Farrar said. The weather service issues the warnings typically between Memorial and Columbus days, whenever there’s a 20-degree difference in water-ocean temperatures.

Several winter cases of hypothermia were reported in Maine this year, including the death of Paul Bouffard, 54, of Ellsworth Jan. 5. Farrar said she is unaware of any summer cases this year.

Farrar warns swimmers and boaters to check water temperatures, currents and tides, wear wetsuits and life jackets, and stick close to land when venturing into the sea.

Farrar said she hopes that Maine tourists will be especially careful of the cold water.

“A lot of visitors are up from Florida this year,” she said, “and they don’t expect it.”

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