National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

16°F

-9°C

Humidity 54%
Wind Speed NW 14 G 24 mph
Barometer 30.00 in (1015.8 mb)
Dewpoint 2°F (-17°C)
Visibility 10.00 mi
Wind Chill2°F (-17°C)
Last update 27 Jan 2:56 am EST
Extended Forecast for

Port Jefferson NY

  • Overnight

    Overnight: Mostly clear, with a low around 18. Wind chill values between zero and 5. Breezy, with a west wind around 23 mph.

    Low: 18 °F

    Mostly Clear
    and Breezy

  • Tuesday

    Tuesday: Increasing clouds, with a high near 21. Wind chill values between zero and 5. Breezy, with a west wind 15 to 21 mph.

    High: 21 °F

    Sunny then
    Partly Sunny
    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 20 to 22 mph.

    Low: 16 °F

    Mostly Clear
    and Breezy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 22. Wind chill values between zero and 10. West wind 10 to 17 mph.

    High: 22 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 14. West wind around 11 mph.

    Low: 14 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 22.

    High: 22 °F

    Mostly Sunny

  • Thursday Night

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

    Low: 11 °F

    Mostly Clear

  • Friday

    Friday: Sunny and cold, with a high near 19.

    High: 19 °F

    Cold

  • Friday Night

    Friday Night: Mostly clear, with a low around 10.

    Low: 10 °F

    Mostly Clear

Detailed Forecast

Overnight
Mostly clear, with a low around 18. Wind chill values between zero and 5. Breezy, with a west wind around 23 mph.
Tuesday
Increasing clouds, with a high near 21. Wind chill values between zero and 5. Breezy, with a west wind 15 to 21 mph.
Tuesday Night
Mostly clear, with a low around 16. Wind chill values between zero and 5. Breezy, with a west wind 20 to 22 mph.
Wednesday
Mostly sunny, with a high near 22. Wind chill values between zero and 10. West wind 10 to 17 mph.
Wednesday Night
Mostly cloudy, with a low around 14. West wind around 11 mph.
Thursday
Mostly sunny, with a high near 22.
Thursday Night
Mostly clear, with a low around 11.
Friday
Sunny and cold, with a high near 19.
Friday Night
Mostly clear, with a low around 10.
Saturday
Mostly sunny, with a high near 23.
Saturday Night
A 40 percent chance of snow. Mostly cloudy, with a low around 18. Windy.
Sunday
A 50 percent chance of snow. Mostly cloudy, with a high near 28. Windy.
Sunday Night
Mostly cloudy, with a low around 22. Windy.
Monday
Mostly sunny, with a high near 30. Blustery.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson NY
 40.96°N 73.08°W (Elev. 3 ft)
Last Update:
1:34 am EST Jan 27, 2026
Forecast Valid:
3am EST Jan 27, 2026-6pm EST Feb 2, 2026
 
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Additional Resources

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