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.

A Few Clouds

56°F

13°C

Humidity 77%
Wind Speed S 8 mph
Barometer 29.95 in (1014.2 mb)
Dewpoint 49°F (9°C)
Visibility 10.00 mi
Last update 11 Mar 9:56 am EDT
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Today

    Today: A 20 percent chance of showers after 2pm. Partly sunny, with a high near 65. South wind 9 to 11 mph.

    High: 65 °F

    Partly Sunny
    then Slight
    Chance
    Showers

  • Tonight

    Tonight: A 40 percent chance of showers and thunderstorms, mainly after 5am. Areas of fog. Otherwise, mostly cloudy, with a low around 41. South wind around 10 mph, with gusts as high as 25 mph.

    Low: 41 °F

    Chance
    Showers and
    Areas Fog

  • Thursday

    Thursday: Rain showers likely before 2pm, then a chance of rain and snow showers. Cloudy, with a temperature rising to near 52 by 10am, then falling to around 41 during the remainder of the day. Northwest wind 10 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. Little or no snow accumulation expected.

    High: 52 °F⇓

    Showers
    Likely then
    Rain/Snow
    Likely

  • Thursday Night

    Thursday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 31. Northwest wind around 7 mph.

    Low: 31 °F

    Decreasing
    Clouds

  • Friday

    Friday: Increasing clouds, with a high near 46. Light and variable wind becoming south 9 to 14 mph in the morning. Winds could gust as high as 24 mph.

    High: 46 °F

    Increasing
    Clouds

  • Friday Night

    Friday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 36.

    Low: 36 °F

    Decreasing
    Clouds

  • Saturday

    Saturday: Sunny, with a high near 48.

    High: 48 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 31.

    Low: 31 °F

    Mostly Cloudy

  • Sunday

    Sunday: Cloudy, with a high near 49.

    High: 49 °F

    Cloudy

Detailed Forecast

Today
A 20 percent chance of showers after 2pm. Partly sunny, with a high near 65. South wind 9 to 11 mph.
Tonight
A 40 percent chance of showers and thunderstorms, mainly after 5am. Areas of fog. Otherwise, mostly cloudy, with a low around 41. South wind around 10 mph, with gusts as high as 25 mph.
Thursday
Rain showers likely before 2pm, then a chance of rain and snow showers. Cloudy, with a temperature rising to near 52 by 10am, then falling to around 41 during the remainder of the day. Northwest wind 10 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. Little or no snow accumulation expected.
Thursday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 31. Northwest wind around 7 mph.
Friday
Increasing clouds, with a high near 46. Light and variable wind becoming south 9 to 14 mph in the morning. Winds could gust as high as 24 mph.
Friday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 36.
Saturday
Sunny, with a high near 48.
Saturday Night
Mostly cloudy, with a low around 31.
Sunday
Cloudy, with a high near 49.
Sunday Night
Showers likely, mainly after 2am. Cloudy, with a low around 40. Chance of precipitation is 70%.
Monday
Showers. High near 54. Chance of precipitation is 90%.
Monday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 28.
Tuesday
Mostly sunny, with a high near 40.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Islip, Long Island Mac Arthur Airport NY
 40.8°N 73.09°W (Elev. 98 ft)
Last Update:
9:48 am EDT Mar 11, 2026
Forecast Valid:
10am EDT Mar 11, 2026-6pm EDT Mar 17, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation