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.

Fair

48°F

9°C

Humidity 74%
Wind Speed Calm
Barometer 29.99 in (1015.4 mb)
Dewpoint 40°F (4°C)
Visibility 10.00 mi
Last update 11 Mar 1:56 am EDT
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Overnight

    Overnight: Patchy fog after 3am. Otherwise, partly cloudy, with a low around 41. Calm wind.

    Low: 41 °F

    Patchy Fog

  • Wednesday

    Wednesday: A 30 percent chance of showers, mainly after 2pm. Patchy fog before 9am. Otherwise, partly sunny, with a high near 55. South wind 5 to 14 mph.

    High: 55 °F

    Chance
    Showers and
    Patchy Fog

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms before 8pm, then a chance of rain and thunderstorms between 8pm and 2am, then a chance of rain after 2am. Mostly cloudy, with a low around 48. South wind around 14 mph, with gusts as high as 25 mph. Chance of precipitation is 40%.

    Low: 48 °F

    Chance
    Showers

  • Thursday

    Thursday: Rain likely before 5pm, then a chance of rain and snow. Cloudy, with a temperature falling to around 43 by 5pm. Northwest wind 14 to 17 mph. Chance of precipitation is 70%. Little or no snow accumulation expected.

    High: 53 °F⇓

    Rain Likely
    then
    Rain/Snow
    Likely

  • Thursday Night

    Thursday Night: A chance of rain and snow before 8pm. Mostly cloudy, then gradually becoming clear, with a low around 29. Northwest wind 8 to 11 mph. Chance of precipitation is 30%.

    Low: 29 °F

    Chance
    Rain/Snow
    then Mostly
    Clear

  • Friday

    Friday: Partly sunny, with a high near 46.

    High: 46 °F

    Partly Sunny

  • Friday Night

    Friday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 35.

    Low: 35 °F

    Decreasing
    Clouds

  • Saturday

    Saturday: Sunny, with a high near 48.

    High: 48 °F

    Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 32.

    Low: 32 °F

    Partly Cloudy

Detailed Forecast

Overnight
Patchy fog after 3am. Otherwise, partly cloudy, with a low around 41. Calm wind.
Wednesday
A 30 percent chance of showers, mainly after 2pm. Patchy fog before 9am. Otherwise, partly sunny, with a high near 55. South wind 5 to 14 mph.
Wednesday Night
A chance of showers and thunderstorms before 8pm, then a chance of rain and thunderstorms between 8pm and 2am, then a chance of rain after 2am. Mostly cloudy, with a low around 48. South wind around 14 mph, with gusts as high as 25 mph. Chance of precipitation is 40%.
Thursday
Rain likely before 5pm, then a chance of rain and snow. Cloudy, with a temperature falling to around 43 by 5pm. Northwest wind 14 to 17 mph. Chance of precipitation is 70%. Little or no snow accumulation expected.
Thursday Night
A chance of rain and snow before 8pm. Mostly cloudy, then gradually becoming clear, with a low around 29. Northwest wind 8 to 11 mph. Chance of precipitation is 30%.
Friday
Partly sunny, with a high near 46.
Friday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 35.
Saturday
Sunny, with a high near 48.
Saturday Night
Partly cloudy, with a low around 32.
Sunday
Mostly cloudy, with a high near 49.
Sunday Night
Rain. Low around 42. Chance of precipitation is 80%.
Monday
Rain. High near 53. Breezy. Chance of precipitation is 80%.
Monday Night
Rain and snow likely. Mostly cloudy, with a low around 28. Chance of precipitation is 60%.
Tuesday
A 30 percent chance of snow. Mostly sunny, with a high near 37.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islip, Long Island Mac Arthur Airport NY
 40.81°N 73.11°W (Elev. 98 ft)
Last Update:
9:48 pm EDT Mar 10, 2026
Forecast Valid:
2am 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