Oppressive heat and humidity blanketing much of the East Coast left its mark across Long Island on Monday with highs in the 90s, warnings to stay indoors and Nassau County opening cooling centers.
The National Weather Service posted a heat advisory early Monday — meaning just being outside could pose a health hazard.
"Drink plenty of fluids, stay in an air-conditioned room if possible, stay out of the sun, and check up on relatives and neighbors," the weather service said in its 3:46 a.m. advisory.
Most parts of Long Island saw the thermometer crest the 90-degree mark by noon with a heat index of more than 100.
The sticky weather got an early start. By 5 a.m. Monday, it was 80 degrees on some parts of Long Island with 85% humidity.
Tuesday brings slight respite from the heat with more sunny skies and a high expected to top out in the mid 80s. There's a 40% chance of showers and thunderstorms early Wednesday, the weather service said. Later Wednesday, the likelihood of showers and thunderstorms bumps up to 50% with a high of 84. Thursday, expect more temperatures in the mid-80s with a 40% chance of showers and thunderstorms through the night.
Sunny skies and a high in the mid-80s are forecast for Friday through the weekend, the weather service said.
The Islip record for this date is 97 degrees, set in 1991. The metropolitan-area record high for July 20 was 101 degrees, recorded in Central Park in 1980.
Considering the dangers posed by the heat, Nassau County Executive Laura Curran announced Monday that cooling centers in Nassau would be open for anyone in need. The cooling centers will remain open Tuesday, county officials said.
Nassau centers were opened Monday at the Cantiague Park Administration Office, 480 West John St. in Hicksville; the Wantagh Administration Building, 1 King Road in Wantagh; and the Mitchel Field Administration Building, 1 Charles Lindbergh Blvd. in Uniondale.
Suffolk does not have county cooling centers and residents are asked to contact their local town governments for cooling center information, officials said.