Saturday morning got off to a soggy start along River...

Saturday morning got off to a soggy start along River Walk Park in Riverhead. Hotter days are forecast ahead. Credit: John Roca

Long Islanders should brace themselves for hot, muggy weather in the coming week with heat index temperatures in Nassau and Suffolk counties possibly rising above 100, affecting the air quality, and making it harder for some to breathe outdoors, according to forecasters.

The National Weather Service is expected to issue a heat advisory Sunday for the western part of the Island as temperatures climb into the mid-90s, according to Jay Engle, a meteorologist with the National Weather Service. 

“The heat advisory is going into effect Sunday for Nassau County and then most of Suffolk, with the exception of the South Fork,” he said.

The heat index, which measures hot how it feels when humidity combines with air temperature, will hit the upper 90s on Sunday, and 100 in New York City and northeast New Jersey.

The forecast for Sunday in Syosset is 95 degrees, Riverhead is expected to reach 93, while Montauk will reach a relatively icy 86 degrees.

It won't stop there: The weather warning will likely remain in effect until midweek.

"It’s called summer," Engle said, noting that the dog days have been coming earlier in the season in recent years. "It takes a while for the ocean to heat up, but now it’s heating up sooner."

By the time Monday rolls around, Stony Brook and Syosset are expected to spike to heat index highs of 101 degrees, and the far southeastern part of the Island will hit 90.

The heat was forecast to stretch into Wednesday afternoon and evening, creating health concerns for vulnerable populations.

The state Department of Environmental Conservation warns that summer heat creates breathing hazards for those with respiratory issues, small children and those who exercise outdoors. The agency issued an air quality health advisory for Sunday for Long Island and the metropolitan area effective until 11 p.m. 

Oppressive summer heat and stagnant air can create air pollutant known as "ground ozone" when the summer sun beats down on car exhaust and industrial emissions — a potentially dangerous byproduct to inhale, according to the DEC.

"People, especially those with cardiovascular disease and those who have respiratory disease, young children, those who exercise outdoors, and those involved in vigorous outdoor work should consider limiting strenuous outdoor physical activity when ozone levels are the highest," the agency said in a statement. 

Smoggy conditions usually alleviate when the sun goes down, the agency said.

After Wednesday, Long Islanders could be hoping for the kind of downpour that many saw Saturday.

“It’s going to last through Wednesday, but then we’re going to catch a break with an increasing chance of thunderstorms that could lift the heat and humidity by Thursday,” Engle said.

Long Islanders should brace themselves for hot, muggy weather in the coming week with heat index temperatures in Nassau and Suffolk counties possibly rising above 100, affecting the air quality, and making it harder for some to breathe outdoors, according to forecasters.

The National Weather Service is expected to issue a heat advisory Sunday for the western part of the Island as temperatures climb into the mid-90s, according to Jay Engle, a meteorologist with the National Weather Service. 

“The heat advisory is going into effect Sunday for Nassau County and then most of Suffolk, with the exception of the South Fork,” he said.

The heat index, which measures hot how it feels when humidity combines with air temperature, will hit the upper 90s on Sunday, and 100 in New York City and northeast New Jersey.

The forecast for Sunday in Syosset is 95 degrees, Riverhead is expected to reach 93, while Montauk will reach a relatively icy 86 degrees.

It won't stop there: The weather warning will likely remain in effect until midweek.

"It’s called summer," Engle said, noting that the dog days have been coming earlier in the season in recent years. "It takes a while for the ocean to heat up, but now it’s heating up sooner."

By the time Monday rolls around, Stony Brook and Syosset are expected to spike to heat index highs of 101 degrees, and the far southeastern part of the Island will hit 90.

The heat was forecast to stretch into Wednesday afternoon and evening, creating health concerns for vulnerable populations.

The state Department of Environmental Conservation warns that summer heat creates breathing hazards for those with respiratory issues, small children and those who exercise outdoors. The agency issued an air quality health advisory for Sunday for Long Island and the metropolitan area effective until 11 p.m. 

Oppressive summer heat and stagnant air can create air pollutant known as "ground ozone" when the summer sun beats down on car exhaust and industrial emissions — a potentially dangerous byproduct to inhale, according to the DEC.

"People, especially those with cardiovascular disease and those who have respiratory disease, young children, those who exercise outdoors, and those involved in vigorous outdoor work should consider limiting strenuous outdoor physical activity when ozone levels are the highest," the agency said in a statement. 

Smoggy conditions usually alleviate when the sun goes down, the agency said.

After Wednesday, Long Islanders could be hoping for the kind of downpour that many saw Saturday.

“It’s going to last through Wednesday, but then we’re going to catch a break with an increasing chance of thunderstorms that could lift the heat and humidity by Thursday,” Engle said.

Join Newsday food writer Andi Berlin as she eats at burger restaurants along Long Beach Road, which she has dubbed the "Hamburger Highway." Credit: Randee Daddona

'This entire street is a hamburger highway' Join Newsday food writer Andi Berlin as she eats at burger restaurants along Long Beach Road, which she has dubbed the "Hamburger Highway."

Join Newsday food writer Andi Berlin as she eats at burger restaurants along Long Beach Road, which she has dubbed the "Hamburger Highway." Credit: Randee Daddona

'This entire street is a hamburger highway' Join Newsday food writer Andi Berlin as she eats at burger restaurants along Long Beach Road, which she has dubbed the "Hamburger Highway."

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