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.

Overcast and Breezy

43°F

6°C

Humidity 86%
Wind Speed SE 21 G 31 mph
Barometer 30.23 in (1023.6 mb)
Dewpoint 39°F (4°C)
Visibility 10.00 mi
Wind Chill34°F (1°C)
Last update 15 Mar 10:56 pm 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

  • Tonight

    Tonight: Showers, with thunderstorms also possible after 5am. Temperature rising to around 48 by 5am. Breezy, with a southeast wind 17 to 22 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 43 °F⇑

    Showers and
    Breezy

  • Monday

    Monday: Showers and possibly a thunderstorm. Patchy fog. High near 56. Windy, with a south wind 22 to 26 mph, with gusts as high as 37 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.

    High: 56 °F

    Showers and
    Patchy Fog

  • Monday Night

    Monday Night: Showers and possibly a thunderstorm before 2am, then a chance of showers. Low around 36. Windy, with a south wind 29 to 36 mph, with gusts as high as 49 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 36 °F

    Showers and
    Windy

  • Tuesday

    Tuesday: A 30 percent chance of showers before 8am. Mostly sunny, with a steady temperature around 38. Wind chill values between 25 and 30. Breezy, with a west wind 22 to 24 mph.

    High: 38 °F

    Breezy.
    Chance
    Showers then
    Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 27. Breezy, with a west wind 17 to 23 mph.

    Low: 27 °F

    Partly Cloudy
    and Breezy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 37.

    High: 37 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 32.

    Low: 32 °F

    Mostly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 42.

    High: 42 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 35.

    Low: 35 °F

    Partly Cloudy

Detailed Forecast

Tonight
Showers, with thunderstorms also possible after 5am. Temperature rising to around 48 by 5am. Breezy, with a southeast wind 17 to 22 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Monday
Showers and possibly a thunderstorm. Patchy fog. High near 56. Windy, with a south wind 22 to 26 mph, with gusts as high as 37 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.
Monday Night
Showers and possibly a thunderstorm before 2am, then a chance of showers. Low around 36. Windy, with a south wind 29 to 36 mph, with gusts as high as 49 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.
Tuesday
A 30 percent chance of showers before 8am. Mostly sunny, with a steady temperature around 38. Wind chill values between 25 and 30. Breezy, with a west wind 22 to 24 mph.
Tuesday Night
Partly cloudy, with a low around 27. Breezy, with a west wind 17 to 23 mph.
Wednesday
Mostly sunny, with a high near 37.
Wednesday Night
Mostly cloudy, with a low around 32.
Thursday
Partly sunny, with a high near 42.
Thursday Night
Partly cloudy, with a low around 35.
Friday
Mostly sunny, with a high near 47.
Friday Night
A 40 percent chance of rain. Mostly cloudy, with a low around 39.
Saturday
A 40 percent chance of rain. Mostly cloudy, with a high near 48.
Saturday Night
Mostly cloudy, with a low around 36. Breezy.
Sunday
Mostly sunny, with a high near 44. Breezy.
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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:
10:28 pm EDT Mar 15, 2026
Forecast Valid:
11pm EDT Mar 15, 2026-6pm EDT Mar 22, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation