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.

Partly Cloudy

58°F

14°C

Humidity 72%
Wind Speed S 12 mph
Barometer 29.96 in (1014.3 mb)
Dewpoint 49°F (9°C)
Visibility 10.00 mi
Last update 11 Mar 10:56 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 around 10 mph, with gusts as high as 20 mph.

    High: 65 °F

    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 40. South wind around 10 mph, with gusts as high as 26 mph.

    Low: 40 °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 15 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 29. Northwest wind around 7 mph.

    Low: 29 °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 around 10 mph, with gusts as high as 20 mph.
Tonight
A 40 percent chance of showers and thunderstorms, mainly after 5am. Areas of fog. Otherwise, mostly cloudy, with a low around 40. South wind around 10 mph, with gusts as high as 26 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 15 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 29. 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 39. 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
 40.78°N 73.09°W (Elev. 49 ft)
Last Update:
9:48 am EDT Mar 11, 2026
Forecast Valid:
11am EDT Mar 11, 2026-6pm EDT Mar 17, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation