It will remain very warm, breezy and humid this evening, with a slight chance for a passing shower or gusty thunderstorm. Otherwise, partly cloudy overnight and into early Thursday with lows in the 70s to near 80 degrees. Air quality remains poor. There will not be much relief overnight.

The South Shore and East End beaches will be places you can get some relief this week as the heat continues to build, but make sure to stay hydrated, use sunscreen and take some breaks. Away from the immediate coastline along the South Shore, actual air temperatures in the 90s to 100 degrees will combine with tropical-like humidity to make it feel like 95 to 110 Thursday through Saturday.

This, plus the poor air quality, can easily lead to heat-related illness if not taking breaks and preparing for the extreme heat. Limit strenuous outdoor activities - do whatever you can to keep your body cool while having some safe, low-energy summer fun. Those with pre-existing respiratory or heart-related illnesses will be most affected, but this is the type of heat and humidity that will affect anyone. Please also check on your pets and remember to check cars for anyone or any pets before walking away.

Reaching an official air temperature at Islip MacArthur Airport here on Long Island of 100 degrees or hotter is extremely rare. It has actually only happened eight times since records have been kept at the airport since 1963 - one of those times was in June of last year. The forecast high on Friday is 100, which could be the ninth time in recorded history. This is not typical summer heat for Long Island. Our normal average highs this time of year are in the lower 80s.

104°F – July 3, 1966 (Islip's all-time record high) 102°F – July 5, 1999 101°F – July 6, 2010 101°F – July 21, 1991 101°F – June 24, 2025 (hottest June day on record) 100°F – July 22, 2011 100°F – August 2, 1975 100°F – August 9, 2001

While this week's heat can be dangerous, we are not expecting any official records to be broken at Islip MacArthur Airport at this time, but Saturday could be close!

THURSDAY: Forecast high: 94 | Record high: 99 (1966)

FRIDAY: Forecast high: 100 | Record high: 104 (1966)

SATURDAY: Forecast high: 95 | Record high: 97 (2010)

TONIGHT: Partly cloudy with a brief shower or thunderstorm possible. Warm and humid. Lows in the 70s to near 80 degrees. Wind: southwest 10 to 20 mph.

THURSDAY: HEAT ALERT - Hazy, hot and humid. This is the start of the peak of this week's extreme heat. Temperatures around 94. It will feel like 95 to 110. Use caution and take breaks from the heat and stay hydrated. Lows near 78 and humid.

FRIDAY: HEAT ALERT - STORM CHANCE - Hazy, hot and humid. Highs around 100. It will feel like 95 to 110. Use extreme caution and take breaks from the heat and stay hydrated. Slight chance for a shower or thunderstorm, but mostly dry. Lows near 77 and humid. Record High is 104, set in 1966.

SATURDAY: HEAT ALERT - FOURTH OF JULY - EVENING STORM CHANCE - Sun and clouds, with a few spotty showers and thunderstorms possible, mostly in the evening. Hot and humid. Highs around 95 can feel like 95 to 105. Use extreme caution and take breaks from the heat and stay hydrated. Lows near 75.

SUNDAY: STILL HOT - A FEW SHOWERS - Sun and clouds, with a few afternoon and evening showers possible. High temperatures around 89. Lows near 71.

MONDAY: HIGH HEAT BREAKS -- Partly sunny, with temperatures around 86. A few showers possible. Lows near 69.

TUESDAY: Mainly sunny. Highs around 85. Lows near 68.

WEDNESDAY: Sun and clouds. Highs around 82 degrees. Lows near 68 degrees.