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.

Overcast

27°F

-3°C

Humidity 35%
Wind Speed N 7 mph
Barometer 30.28 in (1025.5 mb)
Dewpoint 3°F (-16°C)
Visibility 10.00 mi
Wind Chill19°F (-7°C)
Last update 8 Dec 6:56 pm EST
Extended Forecast for

Head of the Harbor NY

  • Tonight

    Tonight: Partly cloudy, with a low around 16. Wind chill values between 10 and 15. North wind 5 to 10 mph.

    Low: 16 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Increasing clouds, with a high near 37. Wind chill values between 10 and 20. Light and variable wind becoming south 5 to 7 mph in the afternoon.

    High: 37 °F

    Increasing
    Clouds

  • Tuesday Night

    Tuesday Night: A 20 percent chance of snow before 1am. Mostly cloudy, with a low around 32. Southwest wind 8 to 11 mph, with gusts as high as 22 mph.

    Low: 32 °F

    Slight Chance
    Snow

  • Wednesday

    Wednesday: Rain likely, mainly after 1pm. Mostly cloudy, with a high near 46. Southwest wind 10 to 16 mph, with gusts as high as 30 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    High: 46 °F

    Chance Rain
    then Rain
    Likely

  • Wednesday Night

    Wednesday Night: A 40 percent chance of rain before 1am. Cloudy, then gradually becoming partly cloudy, with a low around 33. Southwest wind 11 to 14 mph, with gusts as high as 29 mph.

    Low: 33 °F

    Chance Rain

  • Thursday

    Thursday: Mostly sunny, with a high near 41.

    High: 41 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 25.

    Low: 25 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 37.

    High: 37 °F

    Mostly Sunny

  • Friday Night

    Friday Night: A 40 percent chance of snow. Mostly cloudy, with a low around 26.

    Low: 26 °F

    Chance Snow

Detailed Forecast

Tonight
Partly cloudy, with a low around 16. Wind chill values between 10 and 15. North wind 5 to 10 mph.
Tuesday
Increasing clouds, with a high near 37. Wind chill values between 10 and 20. Light and variable wind becoming south 5 to 7 mph in the afternoon.
Tuesday Night
A 20 percent chance of snow before 1am. Mostly cloudy, with a low around 32. Southwest wind 8 to 11 mph, with gusts as high as 22 mph.
Wednesday
Rain likely, mainly after 1pm. Mostly cloudy, with a high near 46. Southwest wind 10 to 16 mph, with gusts as high as 30 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Wednesday Night
A 40 percent chance of rain before 1am. Cloudy, then gradually becoming partly cloudy, with a low around 33. Southwest wind 11 to 14 mph, with gusts as high as 29 mph.
Thursday
Mostly sunny, with a high near 41.
Thursday Night
Partly cloudy, with a low around 25.
Friday
Mostly sunny, with a high near 37.
Friday Night
A 40 percent chance of snow. Mostly cloudy, with a low around 26.
Saturday
A 30 percent chance of snow showers before 7am. Partly sunny, with a high near 38.
Saturday Night
Mostly cloudy, with a low around 22.
Sunday
Mostly sunny, with a high near 33.
Sunday Night
Mostly clear, with a low around 19.
Monday
Mostly sunny, with a high near 34.
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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:
6:30 pm EST Dec 8, 2025
Forecast Valid:
7pm EST Dec 8, 2025-6pm EST Dec 15, 2025
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation