National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Mostly Cloudy

41°F

5°C

Humidity 55%
Wind Speed SW 8 mph
Barometer 30.03 in (1017.0 mb)
Dewpoint 26°F (-3°C)
Visibility 10.00 mi
Wind Chill36°F (2°C)
Last update 7 Dec 4:56 pm EST
Extended Forecast for

Head of the Harbor NY

  • Tonight

    Tonight: Partly cloudy, with a low around 23. West wind 7 to 11 mph becoming northwest after midnight. Winds could gust as high as 24 mph.

    Low: 23 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 29. Wind chill values between 15 and 20. North wind 10 to 15 mph, with gusts as high as 29 mph.

    High: 29 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 17. North wind 3 to 8 mph.

    Low: 17 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Increasing clouds, with a high near 40. Wind chill values between 20 and 25. Calm wind becoming south 5 to 9 mph in the morning.

    High: 40 °F

    Increasing
    Clouds

  • Tuesday Night

    Tuesday Night: A slight chance of rain and snow before 1am, then a slight chance of snow. Mostly cloudy, with a steady temperature around 35. Southwest wind 10 to 13 mph, with gusts as high as 23 mph. Chance of precipitation is 20%.

    Low: 35 °F

    Slight Chance
    Rain/Snow

  • Wednesday

    Wednesday: A 50 percent chance of rain. Mostly cloudy, with a high near 47.

    High: 47 °F

    Chance Rain

  • Wednesday Night

    Wednesday Night: A 30 percent chance of rain before 1am. Cloudy, then gradually becoming partly cloudy, with a low around 35.

    Low: 35 °F

    Chance Rain

  • Thursday

    Thursday: Mostly sunny, with a high near 42.

    High: 42 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: A 30 percent chance of snow after 1am. Mostly cloudy, with a low around 27.

    Low: 27 °F

    Mostly Cloudy
    then Chance
    Snow

Detailed Forecast

Tonight
Partly cloudy, with a low around 23. West wind 7 to 11 mph becoming northwest after midnight. Winds could gust as high as 24 mph.
Monday
Mostly sunny, with a high near 29. Wind chill values between 15 and 20. North wind 10 to 15 mph, with gusts as high as 29 mph.
Monday Night
Partly cloudy, with a low around 17. North wind 3 to 8 mph.
Tuesday
Increasing clouds, with a high near 40. Wind chill values between 20 and 25. Calm wind becoming south 5 to 9 mph in the morning.
Tuesday Night
A slight chance of rain and snow before 1am, then a slight chance of snow. Mostly cloudy, with a steady temperature around 35. Southwest wind 10 to 13 mph, with gusts as high as 23 mph. Chance of precipitation is 20%.
Wednesday
A 50 percent chance of rain. Mostly cloudy, with a high near 47.
Wednesday Night
A 30 percent chance of rain before 1am. Cloudy, then gradually becoming partly cloudy, with a low around 35.
Thursday
Mostly sunny, with a high near 42.
Thursday Night
A 30 percent chance of snow after 1am. Mostly cloudy, with a low around 27.
Friday
A 30 percent chance of rain. Partly sunny, with a high near 38.
Friday Night
A 30 percent chance of snow. Mostly cloudy, with a low around 24.
Saturday
A 30 percent chance of snow. Partly sunny, with a high near 35.
Saturday Night
Partly cloudy, with a low around 21.
Sunday
Mostly sunny, with a high near 33.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Head of the Harbor NY
 40.9°N 73.15°W (Elev. 157 ft)
Last Update:
12:47 pm EST Dec 7, 2025
Forecast Valid:
5pm EST Dec 7, 2025-6pm EST Dec 14, 2025
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation