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

44°F

7°C

Humidity 85%
Wind Speed SE 21 G 30 mph
Barometer 30.13 in (1020.4 mb)
Dewpoint 40°F (4°C)
Visibility 10.00 mi
Wind Chill36°F (2°C)
Last update 16 Mar 12:56 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

  • Overnight

    Overnight: Showers, with thunderstorms also possible after 5am. Low around 39. Southeast wind 10 to 13 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 39 °F

    Showers

  • Monday

    Monday: Showers and possibly a thunderstorm. Patchy fog. High near 58. South wind 14 to 18 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: 58 °F

    Showers and
    Patchy Fog

  • Monday Night

    Monday Night: Showers and possibly a thunderstorm before 2am, then a chance of showers. Low around 34. Breezy, with a south wind 16 to 21 mph, with gusts as high as 47 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 34 °F

    Showers and
    Breezy

  • Tuesday

    Tuesday: A 30 percent chance of showers before 8am. Mostly sunny, with a steady temperature around 38. West wind 14 to 16 mph, with gusts as high as 29 mph.

    High: 38 °F

    Chance
    Showers then
    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 25. West wind 10 to 14 mph, with gusts as high as 24 mph.

    Low: 25 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 38.

    High: 38 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 29.

    Low: 29 °F

    Mostly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 43.

    High: 43 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 33.

    Low: 33 °F

    Partly Cloudy

Detailed Forecast

Overnight
Showers, with thunderstorms also possible after 5am. Low around 39. Southeast wind 10 to 13 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 58. South wind 14 to 18 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 34. Breezy, with a south wind 16 to 21 mph, with gusts as high as 47 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. West wind 14 to 16 mph, with gusts as high as 29 mph.
Tuesday Night
Mostly clear, with a low around 25. West wind 10 to 14 mph, with gusts as high as 24 mph.
Wednesday
Mostly sunny, with a high near 38.
Wednesday Night
Mostly cloudy, with a low around 29.
Thursday
Partly sunny, with a high near 43.
Thursday Night
Partly cloudy, with a low around 33.
Friday
Mostly sunny, with a high near 49.
Friday Night
A 40 percent chance of rain. Mostly cloudy, with a low around 36.
Saturday
A 40 percent chance of rain. Mostly cloudy, with a high near 50.
Saturday Night
Mostly cloudy, with a low around 33.
Sunday
Mostly sunny, with a high near 46.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson NY
 40.93°N 73.06°W (Elev. 161 ft)
Last Update:
10:28 pm EDT Mar 15, 2026
Forecast Valid:
1am EDT Mar 16, 2026-6pm EDT Mar 22, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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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