Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Mostly Cloudy

25°F

-4°C

Humidity 69%
Wind Speed NW 13 mph
Barometer 29.71 in (1006.2 mb)
Dewpoint 16°F (-9°C)
Visibility 10.00 mi
Wind Chill13°F (-11°C)
Last update 26 Jan 3:56 pm EST
Extended Forecast for

Port Jefferson NY

  • This Afternoon

    This Afternoon: A chance of flurries.  Mostly cloudy, with a high near 29. Wind chill values between 15 and 20. Northwest wind around 15 mph.

    High: 29 °F

    Chance
    Flurries

  • Tonight

    Tonight: Mostly cloudy during the early evening, then gradual clearing, with a low around 17. Wind chill values between zero and 10. Windy, with a northwest wind 22 to 26 mph.

    Low: 17 °F

    Gradual
    Clearing and
    Windy

  • Tuesday

    Tuesday: A chance of flurries after noon.  Increasing clouds, with a high near 21. Wind chill values between zero and 5. Breezy, with a west wind 16 to 22 mph.

    High: 21 °F

    Sunny then
    Chance
    Flurries and
    Breezy

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 16. Wind chill values between zero and 5. Breezy, with a west wind 18 to 22 mph.

    Low: 16 °F

    Mostly Clear
    and Breezy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 23. West wind 10 to 17 mph.

    High: 23 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 14.

    Low: 14 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 21.

    High: 21 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 11.

    Low: 11 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny and cold, with a high near 19.

    High: 19 °F

    Cold

Detailed Forecast

This Afternoon
A chance of flurries. Mostly cloudy, with a high near 29. Wind chill values between 15 and 20. Northwest wind around 15 mph.
Tonight
Mostly cloudy during the early evening, then gradual clearing, with a low around 17. Wind chill values between zero and 10. Windy, with a northwest wind 22 to 26 mph.
Tuesday
A chance of flurries after noon. Increasing clouds, with a high near 21. Wind chill values between zero and 5. Breezy, with a west wind 16 to 22 mph.
Tuesday Night
Mostly clear, with a low around 16. Wind chill values between zero and 5. Breezy, with a west wind 18 to 22 mph.
Wednesday
Mostly sunny, with a high near 23. West wind 10 to 17 mph.
Wednesday Night
Mostly cloudy, with a low around 14.
Thursday
Mostly sunny, with a high near 21.
Thursday Night
Mostly clear, with a low around 11.
Friday
Mostly sunny and cold, with a high near 19.
Friday Night
Partly cloudy, with a low around 12.
Saturday
Mostly sunny, with a high near 24.
Saturday Night
A 30 percent chance of snow. Mostly cloudy, with a low around 18.
Sunday
A 30 percent chance of snow. Partly sunny, with a high near 28. Blustery.
Sunday Night
Mostly cloudy, with a low around 21. Blustery.
Monday
Mostly sunny, with a high near 30.
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ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson NY
 40.96°N 73.08°W (Elev. 3 ft)
1:55 pm EST Jan 26, 2026
4pm EST Jan 26, 2026-6pm EST Feb 2, 2026
 
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Additional Resources

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