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

64°F

18°C

Humidity 75%
Wind Speed Calm
Barometer 30.19 in (1022.3 mb)
Dewpoint 56°F (13°C)
Visibility 10.00 mi
Last update 29 Aug 10:56 pm EDT
Extended Forecast for

Islip NY

  • Tonight

    Tonight: Mostly clear, with a low around 63. Southwest wind 3 to 5 mph.

    Low: 63 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 81. Southwest wind 5 to 13 mph.

    High: 81 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Showers and thunderstorms likely before 2am, then a chance of showers. Mostly cloudy, with a low around 67. Southwest wind 5 to 10 mph becoming light west after midnight. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 67 °F

    Showers
    Likely

  • Monday

    Monday: Partly sunny, with a high near 80. Calm wind becoming north around 5 mph in the afternoon.

    High: 80 °F

    Partly Sunny

  • Monday Night

    Monday Night: A 40 percent chance of showers. Mostly cloudy, with a low around 67. South wind 3 to 5 mph.

    Low: 67 °F

    Chance
    Showers

  • Tuesday

    Tuesday: A 50 percent chance of showers and thunderstorms after 2pm. Mostly cloudy, with a high near 81.

    High: 81 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 69. Chance of precipitation is 50%.

    Low: 69 °F

    Chance
    T-storms

  • Wednesday

    Wednesday: A 30 percent chance of showers after 2pm. Mostly cloudy, with a high near 82.

    High: 82 °F

    Mostly Cloudy
    then Chance
    Showers

  • Wednesday Night

    Wednesday Night: Showers likely, mainly after 2am. Mostly cloudy, with a low around 69. Chance of precipitation is 60%.

    Low: 69 °F

    Showers
    Likely

Detailed Forecast

Tonight
Mostly clear, with a low around 63. Southwest wind 3 to 5 mph.
Sunday
Mostly sunny, with a high near 81. Southwest wind 5 to 13 mph.
Sunday Night
Showers and thunderstorms likely before 2am, then a chance of showers. Mostly cloudy, with a low around 67. Southwest wind 5 to 10 mph becoming light west after midnight. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Monday
Partly sunny, with a high near 80. Calm wind becoming north around 5 mph in the afternoon.
Monday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 67. South wind 3 to 5 mph.
Tuesday
A 50 percent chance of showers and thunderstorms after 2pm. Mostly cloudy, with a high near 81.
Tuesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 69. Chance of precipitation is 50%.
Wednesday
A 30 percent chance of showers after 2pm. Mostly cloudy, with a high near 82.
Wednesday Night
Showers likely, mainly after 2am. Mostly cloudy, with a low around 69. Chance of precipitation is 60%.
Thursday
Showers likely, mainly before 8am. Partly sunny, with a high near 83. Chance of precipitation is 60%.
Thursday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 67.
Friday
Mostly sunny, with a high near 80.
Friday Night
A 30 percent chance of showers. Partly cloudy, with a low around 63.
Saturday
Mostly sunny, with a high near 77.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islip NY
 40.73°N 73.22°W (Elev. 7 ft)
Last Update:
2:24 pm EDT Aug 29, 2026
Forecast Valid:
11pm EDT Aug 29, 2026-6pm EDT Sep 5, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation