Long Island is currently under a heat advisory as temperatures approach 90 degrees Fahrenheit, with the heat index making it feel even hotter, close to 100 degrees. The advisory, initially set to end at 7 p.m. on Sunday, has been extended until 7 p.m. on Monday for Nassau and western Suffolk Counties, according to the National Weather Service.

On Monday, after an overnight low of about 72 degrees, the forecast predicts sunny skies with a high of approximately 88 degrees. However, the humidity will elevate the heat index, making it feel like 95 degrees. Meteorologist James Tomasini from the weather service's Upton office emphasized the importance of staying hydrated and taking breaks in shaded areas, especially for those engaged in outdoor activities.

“Monday is also going to be a similar day,” Tomasini noted, adding that there will be increased chances of showers and thunderstorms in the late afternoon and evening. The weather service has urged outdoor workers to take frequent breaks and to ensure that children and pets are not left in vehicles.

To combat heat stress, the weather service recommends drinking beverages with electrolytes, applying sunscreen every two hours, and wearing lightweight, loose-fitting clothing. The heat is expected to persist, with high temperatures in the mid to upper 80s on Tuesday and Wednesday, and a 30% chance of rain on Thursday.

As the summer heat continues, understanding the heat index becomes crucial for safety. The heat index is a measure that combines air temperature and humidity to determine the apparent temperature, or how hot it actually feels to the human body. This is especially important for planning outdoor activities and ensuring adequate hydration.