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.

Mostly Cloudy

74°F

23°C

Humidity 91%
Wind Speed W 6 mph
Barometer 30.01 in (1016.1 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Last update 28 Aug 7:56 pm EDT
Extended Forecast for

Port Jefferson Station NY

  • Tonight

    Tonight: Partly cloudy, with a low around 61. Light northwest wind becoming north 5 to 9 mph in the evening.

    Low: 61 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 76. North wind 3 to 8 mph.

    High: 76 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 63. Calm wind becoming southwest around 5 mph after midnight.

    Low: 63 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 80. Southwest wind 5 to 11 mph.

    High: 80 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 69. Southwest wind 7 to 9 mph. Chance of precipitation is 50%.

    Low: 69 °F

    Chance
    Showers

  • Monday

    Monday: Partly sunny, with a high near 80.

    High: 80 °F

    Partly Sunny

  • Monday Night

    Monday Night: A 40 percent chance of showers after 2am. Mostly cloudy, with a low around 67.

    Low: 67 °F

    Mostly Cloudy
    then Chance
    Showers

  • Tuesday

    Tuesday: A 40 percent chance of showers. Mostly cloudy, with a high near 79.

    High: 79 °F

    Chance
    Showers

  • Tuesday Night

    Tuesday Night: A chance of showers, with thunderstorms also possible after 8pm. Mostly cloudy, with a low around 68. Chance of precipitation is 50%.

    Low: 68 °F

    Chance
    T-storms

Detailed Forecast

Tonight
Partly cloudy, with a low around 61. Light northwest wind becoming north 5 to 9 mph in the evening.
Saturday
Sunny, with a high near 76. North wind 3 to 8 mph.
Saturday Night
Mostly clear, with a low around 63. Calm wind becoming southwest around 5 mph after midnight.
Sunday
Mostly sunny, with a high near 80. Southwest wind 5 to 11 mph.
Sunday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 69. Southwest wind 7 to 9 mph. Chance of precipitation is 50%.
Monday
Partly sunny, with a high near 80.
Monday Night
A 40 percent chance of showers after 2am. Mostly cloudy, with a low around 67.
Tuesday
A 40 percent chance of showers. Mostly cloudy, with a high near 79.
Tuesday Night
A chance of showers, with thunderstorms also possible after 8pm. Mostly cloudy, with a low around 68. Chance of precipitation is 50%.
Wednesday
A 40 percent chance of showers. Mostly cloudy, with a high near 81.
Wednesday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 69.
Thursday
A 40 percent chance of showers. Partly sunny, with a high near 82.
Thursday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 66.
Friday
Mostly sunny, with a high near 79.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson Station NY
 40.93°N 73.06°W (Elev. 161 ft)
Last Update:
2:11 pm EDT Aug 28, 2026
Forecast Valid:
8pm EDT Aug 28, 2026-6pm EDT Sep 4, 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