Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Overcast

42°F

6°C

Humidity 85%
Wind Speed SE 13 G 22 mph
Barometer 29.96 in (1014.5 mb)
Dewpoint 38°F (3°C)
Visibility 10.00 mi
Wind Chill35°F (2°C)
Last update 22 Mar 5:56 am EDT
Extended Forecast for

Port Jefferson NY

  • Today

    Today: A 30 percent chance of rain, mainly after 5pm.  Mostly cloudy, with a high near 53. South wind 6 to 10 mph.

    High: 53 °F

    Chance Rain

  • Tonight

    Tonight: Rain, mainly between 8pm and 11pm, then showers after 11pm.  Low around 38. South wind around 5 mph becoming light and variable.  Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 38 °F

    Rain

  • Monday

    Monday: A 40 percent chance of rain before 2pm.  Cloudy, then gradually becoming mostly sunny, with a high near 45. North wind 11 to 13 mph.

    High: 45 °F

    Chance Rain

  • Monday Night

    Monday Night: Mostly clear, with a low around 30. Northwest wind 9 to 11 mph.

    Low: 30 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 45. Northwest wind around 7 mph becoming southwest in the afternoon.

    High: 45 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Increasing clouds, with a low around 34.

    Low: 34 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: Mostly cloudy, with a high near 49.

    High: 49 °F

    Mostly Cloudy

  • Wednesday Night

    Wednesday Night: A 30 percent chance of rain after 2am.  Mostly cloudy, with a low around 38.

    Low: 38 °F

    Mostly Cloudy
    then Chance
    Rain

  • Thursday

    Thursday: A 30 percent chance of rain.  Mostly cloudy, with a high near 51.

    High: 51 °F

    Chance Rain

Detailed Forecast

Today
A 30 percent chance of rain, mainly after 5pm. Mostly cloudy, with a high near 53. South wind 6 to 10 mph.
Tonight
Rain, mainly between 8pm and 11pm, then showers after 11pm. Low around 38. South wind around 5 mph becoming light and variable. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Monday
A 40 percent chance of rain before 2pm. Cloudy, then gradually becoming mostly sunny, with a high near 45. North wind 11 to 13 mph.
Monday Night
Mostly clear, with a low around 30. Northwest wind 9 to 11 mph.
Tuesday
Sunny, with a high near 45. Northwest wind around 7 mph becoming southwest in the afternoon.
Tuesday Night
Increasing clouds, with a low around 34.
Wednesday
Mostly cloudy, with a high near 49.
Wednesday Night
A 30 percent chance of rain after 2am. Mostly cloudy, with a low around 38.
Thursday
A 30 percent chance of rain. Mostly cloudy, with a high near 51.
Thursday Night
Rain likely, mainly after 2am. Mostly cloudy, with a low around 41. Chance of precipitation is 60%.
Friday
Rain likely. Partly sunny, with a high near 49. Chance of precipitation is 60%.
Friday Night
Partly cloudy, with a low around 26.
Saturday
Sunny, with a high near 41.
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ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson NY
 40.93°N 73.06°W (Elev. 161 ft)
2:51 am EDT Mar 22, 2026
6am EDT Mar 22, 2026-6pm EDT Mar 28, 2026
 
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Additional Resources

Radar & Satellite Image

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Hourly Weather Forecast

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