Abnormally hot and humid weather is expected across Long Island on Saturday as a southerly flow out of the southwest brings in air 10 degrees above normal, the National Weather Service said.

High temperatures will generally be in the mid-80s Saturday, said Faye Barthold, a meteorologist with the weather service’s Upton bureau, while the Twin Forks will stay a little cooler.

Matt Hammer, a meteorologist with News 12 Long Island, said a mix of sun and clouds with breezy winds — gusting at 20 to 25 mph — is “overall going to be a nice start to the weekend.”

The normal high for this time of year at Long Island MacArthur Airport is about 76 degrees, Barthold said.

Those hitting the beaches this weekend — some of which have been kept open for a last dose of summery weather — can expect water temperatures off Jones Beach to be around 71 degrees and at Robert Moses State Park, Barthold said.

A high rip-current risk advisory is in effect for Nassau County’s ocean beaches Saturday, while Suffolk beaches have been designated a moderate risk.

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A chance of scattered showers or thunderstorms begins to heighten overnight Saturday into Sunday morning, Barthold said, while the temperatures drop into the low to mid-70s. The north and western parts of Long Island have the best chances for precipitation, Hammer said.

Any precipitation should clear by midmorning to early afternoon Sunday, Barthold said.

Humidity will begin to drop Sunday, but the temperatures will remain in the mid-80s, Barthold said, while sunshine increases in the afternoon, according to Hammer.It won’t be until overnight Sunday into Monday that temperatures begin to cool down, with a low expected in the mid-50s, and will return to about normal for this time of year on Monday, when temperatures will be in the mid-70s.

The week ahead “looks gorgeous overall,” Hammer said, with a slight chance of a shower on Wednesday until sunshine returns with high temperatures in the lower 70s on Thursday and Friday.