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.

Fog and Breezy

54°F

12°C

Humidity 97%
Wind Speed S 22 G 36 mph
Barometer 29.76 in (1007.8 mb)
Dewpoint 53°F (12°C)
Visibility 0.13 mi
Wind Chill49°F (9°C)
Last update 16 Mar 10:56 am EDT
Extended Forecast for

Port Jefferson NY

Wind Advisory March 16, 02:00pm until March 17, 04:00am
Click here for hazard details and duration
Wind Advisory

  • Today

    Today: Showers and possibly a thunderstorm. Areas of fog. High near 56. Windy, with a south wind 25 to 29 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    High: 56 °F

    Showers and
    Areas Fog

  • Tonight

    Tonight: Showers and possibly a thunderstorm before 2am, then a chance of showers. Areas of fog before 2am. Low around 36. Very windy, with a south wind 32 to 41 mph becoming west after midnight. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 36 °F

    Showers and
    Areas Fog

  • Tuesday

    Tuesday: Mostly sunny, with a high near 40. Wind chill values between 25 and 30. Breezy, with a west wind 22 to 24 mph.

    High: 40 °F

    Mostly Sunny
    and Breezy

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 28. Wind chill values between 15 and 20. Breezy, with a west wind 17 to 21 mph.

    Low: 28 °F

    Partly Cloudy
    and Breezy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 36. Northwest wind 6 to 11 mph becoming southwest in the afternoon.

    High: 36 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 31.

    Low: 31 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 42.

    High: 42 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 37.

    Low: 37 °F

    Mostly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 48.

    High: 48 °F

    Mostly Sunny

Detailed Forecast

Today
Showers and possibly a thunderstorm. Areas of fog. High near 56. Windy, with a south wind 25 to 29 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Tonight
Showers and possibly a thunderstorm before 2am, then a chance of showers. Areas of fog before 2am. Low around 36. Very windy, with a south wind 32 to 41 mph becoming west after midnight. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.
Tuesday
Mostly sunny, with a high near 40. Wind chill values between 25 and 30. Breezy, with a west wind 22 to 24 mph.
Tuesday Night
Partly cloudy, with a low around 28. Wind chill values between 15 and 20. Breezy, with a west wind 17 to 21 mph.
Wednesday
Mostly sunny, with a high near 36. Northwest wind 6 to 11 mph becoming southwest in the afternoon.
Wednesday Night
Mostly cloudy, with a low around 31.
Thursday
Mostly sunny, with a high near 42.
Thursday Night
Mostly cloudy, with a low around 37.
Friday
Mostly sunny, with a high near 48.
Friday Night
Mostly cloudy, with a low around 36.
Saturday
A chance of rain and snow. Mostly cloudy, with a high near 45. Chance of precipitation is 40%.
Saturday Night
A 30 percent chance of rain. Mostly cloudy, with a low around 36.
Sunday
A 30 percent chance of rain. Partly sunny, with a high near 43.
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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:
11:41 am EDT Mar 16, 2026
Forecast Valid:
11am EDT Mar 16, 2026-6pm EDT Mar 22, 2026
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation