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.

Mostly Cloudy

47°F

8°C

Humidity 42%
Wind Speed NW 15 mph
Barometer 30.15 in (1020.9 mb)
Dewpoint 25°F (-4°C)
Visibility 10.00 mi
Wind Chill41°F (5°C)
Last update 6 Nov 8:56 pm EST
Extended Forecast for

Port Jefferson NY

Frost Advisory November 7, 12:00am until November 7, 08:00am
Click here for hazard details and duration
Frost Advisory

  • Tonight

    Tonight: Areas of frost after 4am. Otherwise, mostly clear, with a low around 37. Northwest wind 6 to 14 mph.

    Low: 37 °F

    Mostly Clear
    then Areas
    Frost

  • Friday

    Friday: Areas of frost before 7am. Otherwise, mostly sunny, with a high near 60. Breezy, with a south wind 6 to 11 mph increasing to 18 to 23 mph in the afternoon.

    High: 60 °F

    Areas Frost
    then Partly
    Sunny and
    Breezy

  • Friday Night

    Friday Night: Light rain likely, mainly after 10pm. Cloudy, with a low around 57. Windy, with a south wind 18 to 26 mph. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch possible.

    Low: 57 °F

    Light Rain
    Likely and
    Windy

  • Saturday

    Saturday: A 50 percent chance of light rain before 1pm. Mostly cloudy, then gradually becoming sunny, with a high near 62. West wind 8 to 14 mph.

    High: 62 °F

    Chance Light
    Rain

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 53. Northwest wind 7 to 9 mph becoming east after midnight.

    Low: 53 °F

    Partly Cloudy

  • Sunday

    Sunday: Rain likely, mainly after 1pm. Mostly cloudy, with a high near 61. Chance of precipitation is 70%. New precipitation amounts between a quarter and half of an inch possible.

    High: 61 °F

    Rain Likely

  • Sunday Night

    Sunday Night: Rain likely, mainly before 1am. Mostly cloudy, with a low around 48. Chance of precipitation is 60%.

    Low: 48 °F

    Rain Likely

  • Monday

    Monday: A 30 percent chance of rain before 1pm. Partly sunny, with a high near 52.

    High: 52 °F

    Chance Rain

  • Monday Night

    Monday Night: Partly cloudy, with a low around 37. Breezy.

    Low: 37 °F

    Partly Cloudy
    and Breezy

Detailed Forecast

Tonight
Areas of frost after 4am. Otherwise, mostly clear, with a low around 37. Northwest wind 6 to 14 mph.
Friday
Areas of frost before 7am. Otherwise, mostly sunny, with a high near 60. Breezy, with a south wind 6 to 11 mph increasing to 18 to 23 mph in the afternoon.
Friday Night
Light rain likely, mainly after 10pm. Cloudy, with a low around 57. Windy, with a south wind 18 to 26 mph. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch possible.
Saturday
A 50 percent chance of light rain before 1pm. Mostly cloudy, then gradually becoming sunny, with a high near 62. West wind 8 to 14 mph.
Saturday Night
Partly cloudy, with a low around 53. Northwest wind 7 to 9 mph becoming east after midnight.
Sunday
Rain likely, mainly after 1pm. Mostly cloudy, with a high near 61. Chance of precipitation is 70%. New precipitation amounts between a quarter and half of an inch possible.
Sunday Night
Rain likely, mainly before 1am. Mostly cloudy, with a low around 48. Chance of precipitation is 60%.
Monday
A 30 percent chance of rain before 1pm. Partly sunny, with a high near 52.
Monday Night
Partly cloudy, with a low around 37. Breezy.
Veterans Day
Mostly sunny, with a high near 46. Breezy.
Tuesday Night
Partly cloudy, with a low around 42. Windy.
Wednesday
Partly sunny, with a high near 52. Breezy.
Wednesday Night
Partly cloudy, with a low around 47. Breezy.
Thursday
Mostly sunny, with a high near 51. 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:
1:21 pm EST Nov 6, 2025
Forecast Valid:
9pm EST Nov 6, 2025-6pm EST Nov 13, 2025
 
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Additional Resources

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