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

55°F

13°C

Humidity 77%
Wind Speed SE 5 mph
Barometer 30.18 in (1021.8 mb)
Dewpoint 48°F (9°C)
Visibility 10.00 mi
Wind Chill54°F (12°C)
Last update 15 Oct 8:56 pm EDT
Extended Forecast for

Stony Brook NY

  • Tonight

    Tonight: Showers likely after 5am. Increasing clouds, with a temperature falling to near 53 by 11pm, then rising to around 57 during the remainder of the night. Southeast wind around 7 mph. Chance of precipitation is 60%.

    Low: 53 °F⇑

    Partly Cloudy
    then Showers
    Likely

  • Friday

    Friday: Showers, with thunderstorms also possible after 2pm. High near 72. Southwest wind 10 to 13 mph, with gusts as high as 23 mph. Chance of precipitation is 90%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 72 °F

    Showers then
    Chance
    Showers

  • Friday Night

    Friday Night: Showers and thunderstorms before 2am, then showers likely. Low around 47. West wind 10 to 15 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 47 °F

    Showers then
    Showers
    Likely

  • Saturday

    Saturday: Showers likely before 8am. Cloudy through mid morning, then gradual clearing, with a high near 54. North wind 16 to 18 mph. Chance of precipitation is 60%.

    High: 54 °F

    Showers
    Likely then
    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 41. North wind 11 to 15 mph.

    Low: 41 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 57.

    High: 57 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 46.

    Low: 46 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 61.

    High: 61 °F

    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 49.

    Low: 49 °F

    Partly Cloudy

Detailed Forecast

Tonight
Showers likely after 5am. Increasing clouds, with a temperature falling to near 53 by 11pm, then rising to around 57 during the remainder of the night. Southeast wind around 7 mph. Chance of precipitation is 60%.
Friday
Showers, with thunderstorms also possible after 2pm. High near 72. Southwest wind 10 to 13 mph, with gusts as high as 23 mph. Chance of precipitation is 90%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Friday Night
Showers and thunderstorms before 2am, then showers likely. Low around 47. West wind 10 to 15 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Saturday
Showers likely before 8am. Cloudy through mid morning, then gradual clearing, with a high near 54. North wind 16 to 18 mph. Chance of precipitation is 60%.
Saturday Night
Mostly clear, with a low around 41. North wind 11 to 15 mph.
Sunday
Sunny, with a high near 57.
Sunday Night
Mostly clear, with a low around 46.
Monday
Sunny, with a high near 61.
Monday Night
Partly cloudy, with a low around 49.
Tuesday
Mostly sunny, with a high near 64.
Tuesday Night
Partly cloudy, with a low around 51.
Wednesday
Sunny, with a high near 64.
Wednesday Night
Mostly clear, with a low around 49.
Thursday
Mostly sunny, with a high near 60.
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ABOUT THIS FORECAST

 
Point Forecast:
Stony Brook NY
 40.92°N 73.15°W (Elev. 36 ft)
Last Update:
2:36 pm EDT Oct 15, 2026
Forecast Valid:
9pm EDT Oct 15, 2026-6pm EDT Oct 22, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

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