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

63°F

17°C

Humidity 70%
Wind Speed Calm
Barometer 29.89 in (1012.2 mb)
Dewpoint 53°F (12°C)
Visibility 10.00 mi
Last update 15 Apr 12:56 am EDT
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Overnight

    Overnight: Patchy fog after 2am. Otherwise, partly cloudy, with a low around 54. Southwest wind around 6 mph.

    Low: 54 °F

    Patchy Fog

  • Wednesday

    Wednesday: Patchy fog before 8am. Otherwise, mostly sunny, with a high near 77. Light southwest wind increasing to 5 to 10 mph in the morning.

    High: 77 °F

    Patchy Fog
    then Sunny

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms before 2am, then a slight chance of showers. Mostly cloudy, with a low around 54. Southwest wind 3 to 6 mph. Chance of precipitation is 30%.

    Low: 54 °F

    Chance
    T-storms then
    Chance
    Showers

  • Thursday

    Thursday: Partly sunny, with a high near 74. Light southwest wind increasing to 5 to 9 mph in the morning.

    High: 74 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: A 20 percent chance of showers after 2am. Mostly cloudy, with a low around 54. Southwest wind 3 to 6 mph.

    Low: 54 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

  • Friday

    Friday: A 40 percent chance of showers after 2pm. Partly sunny, with a high near 71.

    High: 71 °F

    Partly Sunny
    then Chance
    Showers

  • Friday Night

    Friday Night: A 30 percent chance of showers before 8pm. Mostly cloudy, with a low around 50.

    Low: 50 °F

    Chance
    Showers then
    Mostly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 61.

    High: 61 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 47.

    Low: 47 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Patchy fog after 2am. Otherwise, partly cloudy, with a low around 54. Southwest wind around 6 mph.
Wednesday
Patchy fog before 8am. Otherwise, mostly sunny, with a high near 77. Light southwest wind increasing to 5 to 10 mph in the morning.
Wednesday Night
A chance of showers and thunderstorms before 2am, then a slight chance of showers. Mostly cloudy, with a low around 54. Southwest wind 3 to 6 mph. Chance of precipitation is 30%.
Thursday
Partly sunny, with a high near 74. Light southwest wind increasing to 5 to 9 mph in the morning.
Thursday Night
A 20 percent chance of showers after 2am. Mostly cloudy, with a low around 54. Southwest wind 3 to 6 mph.
Friday
A 40 percent chance of showers after 2pm. Partly sunny, with a high near 71.
Friday Night
A 30 percent chance of showers before 8pm. Mostly cloudy, with a low around 50.
Saturday
Partly sunny, with a high near 61.
Saturday Night
Mostly cloudy, with a low around 47.
Sunday
A 50 percent chance of showers after 8am. Mostly cloudy, with a high near 60.
Sunday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 40.
Monday
Mostly sunny, with a high near 51.
Monday Night
Mostly clear, with a low around 35.
Tuesday
Sunny, with a high near 51.
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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:
9:09 pm EDT Apr 14, 2026
Forecast Valid:
1am EDT Apr 15, 2026-6pm EDT Apr 21, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation