Long Island weather: Heat wave kicks in on Sunday

If you like high temperatures in the 90s, you're in for a treat.

A heat advisory has been issued for parts of Long Island, from noon Sunday through 8 p.m. Monday, as a three-day heat wave closes its grip the region, according to the National Weather Service.

The highs for the next three days are forecast to eclipse 90: Sunday will see a high of 91, Monday a high of 93, and then Tuesday is predicted to top out at 91 again.

But it will feel even hotter, according to the weather experts.

The heat index — a measure of how hot it really feels when relative humidity is factored in with air temperature — is forecast to be in the mid- to high 90s Sunday across much of Long Island, and in the high 90s both Monday and Tuesday.

An air quality health advisory also has been issued for Long Island on Sunday, Suffolk County officials said. The pollutant of concern is ozone.

Nassau County’s cooling centers will be available Saturday through Wednesday, County Executive Laura Curran said. And residents can cool off in pools whose hours will be extended.

Cooling center locations:

• Cantiague Park Administration Office conference room, 480 W. John St., Hicksville. Open 10 a.m.-8 p.m.
• Mitchel Field Administration Building, first floor, 1 Charles Lindbergh Blvd., Uniondale. Open 10 a.m. - 6 p.m.
• Wantagh Administration Building community room, 1 King Rd., Wantagh. Open 10 a.m.-6 p.m.

Pools with extended hours:

• Cantiague Park Pool, 480 W. John St., Hicksville, Saturday-Tuesday, 10 a.m.-7 p.m.
• Wantagh Park Pool, 1 King Rd., Wantagh, Saturday-Tuesday, 10 a.m.-7 p.m.

Nassau County pools are open seven days a week to county residents. 

Those heading to beaches for relief might start out early: By Saturday afternoon, as sunny skies helped drive temperatures well into the 80s, several beaches and state parks across the Island had reached capacity and were no longer accepting new visitors.

Robert Moses State Park was at capacity by 10:30 a.m., according to the state parks' website. Hither Hills State Park in Montauk was at capacity by 11:15 a.m. Wildwood State Park in Wading River was at capacity by 12:30 p.m.

At Jones Beach, fields 2, 3 and 6, as well as the West Bathhouse Pool, also were closed to incoming visitors and traffic, the state parks' website said.

The beaches at Point Lookout, Lido and Lido West had all reached maximum capacity, Hempstead officials said on Twitter.

Nickerson Beach was also at capacity, Nassau police said in a release shortly before 2 p.m.

And in Suffolk, the county parks department said on Facebook that the Cupsogue outer beach and the Shinnecock East oceanside beach were at capacity. 

Meanwhile, Valley Grove Beach in Eatons Neck was closed to bathing Saturday due to the finding of bacteria in excess of acceptable criteria. Tanner Park Beach in Copiague also remained closed to bathing.

According to Suffolk County Commissioner of Health Dr. Gregson Pigott, bathing in bacteria-contaminated water can result in gastrointestinal illness, as well as infections of the eyes, ears, nose and throat.

The beaches will reopen when further testing reveals that the bacteria have subsided to acceptable levels.

Tuesday could bring some relief from the heat, but not much: Showers and thunderstorms are forecast to develop into Tuesday night "ahead of an approaching cold front," the weather service said.

Then look for sun, and temperatures to hover in the mid-80s from Wednesday to Friday.

"The cold front should start to push offshore by late Wednesday as high pressure begins to build in allowing for drier conditions through the end of the week," the weather service said.

With Joan Gralla