High heat, humidity move into region this week, though Long Island forecast to be spared the worst

The start of summer is coming in hot.

Long Island is bracing for the heat this week, as high temperatures and uncomfortable humidity move into the region starting Tuesday, with some areas, such as northern Nassau and western Suffolk counties, forecast to reach a heat index of about 100 degrees by Friday, according to the National Weather Service.

The first sign of the coming heat is expected to arrive by Tuesday afternoon, with temperatures on parts of Long Island forecast to hit the upper 80s. The heat will intensify Wednesday, when high temperatures climb into the low 90s, with a heat index that could come close to 95 with humidity, according to the weather service.

Thursday, the official start of summer, will continue to see temperatures rising. Then Friday, highs will top 94, but humidity could make it feel anywhere from 95 to up to 101, according to the forecast. Temperatures are expected to remain about 10 degrees cooler near the South Shore beaches.

Temperatures are expected to be even hotter upstate. Across New York, day and nighttime temperatures will be about 5 to 15 degrees above normal.

Gov. Kathy Hochul announced Monday that the state was activating 50 members of the National Guard to provide support. The state Department of Health has also offered guidance to all hospitals and nursing homes.

“Heat waves can be dangerous — with one expected this week, I encourage New Yorkers to take precautions necessary to stay safe and avoid exhaustion,” Hochul said in a statement. “Keep an eye on your local forecast, stay hydrated and postpone outdoor activity as much as possible.”

The New York State Department of Public Service is also tracking electric system conditions and working with utility leaders to prepare for extreme heat. If utilities are near reaching capacity, the state DPS will activate its “standard peak load reduction program” for all New York State agencies and voluntary Emergency Response Demand Program to limit use as necessary. The state has 5,500 workers on standby to respond to damage assessment, response, repair and restoration efforts across the state as needed.

The weather service considers a heat wave as three consecutive days topping 90 degrees.

Extreme heat is increasing across the country due to global warming, with this year expected to set records as the hottest year ever, according to NOAA’s National Centers for Environmental Information.

The U.S. Centers for Disease Control and Prevention said the heat “is projected to be more frequent and intense.” The CDC estimates that more than 1,200 people across the country die of extreme heat every year.

The heat comes as a result of a high-pressure system known as a “heat dome,” which may trap a mass of hot temperatures and humidity over the Northeast, according to the weather service.

The forecast is expected to remain hot and humid, but dry, with few showers forecast before the weekend. The weekend temperatures don’t look like there will be much relief, with highs expected to remain near 90.

There is still good air quality with the incoming heat, but officials have warned residents to monitor the air quality for the potential of high ozone levels, which can affect sensitive individuals.

By John Asbury

john.asbury@newsday.comJohnAsbury

John Asbury is a breaking news and general assignment reporter. He has been with Newsday since 2014 and previously worked at The Press-Enterprise in Riverside, California.