National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Mostly Cloudy

78°F

26°C

Humidity 76%
Wind Speed SW 5 mph
Barometer 29.87 in (1011.4 mb)
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 13 Aug 7:56 pm EDT
Extended Forecast for

Sayville NY

  • Tonight

    Tonight: Partly cloudy, with a low around 68. West wind around 6 mph becoming light and variable in the evening.

    Low: 68 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 84. Light and variable wind becoming southwest 5 to 7 mph in the morning.

    High: 84 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 65. Light and variable wind.

    Low: 65 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 82. Northeast wind around 7 mph.

    High: 82 °F

    Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 66. South wind around 5 mph becoming calm in the evening.

    Low: 66 °F

    Partly Cloudy

  • Sunday

    Sunday: A 50 percent chance of showers after 2pm. Partly sunny, with a high near 81.

    High: 81 °F

    Mostly Sunny
    then Chance
    Showers

  • Sunday Night

    Sunday Night: A chance of showers before 8pm, then showers and possibly a thunderstorm between 8pm and 2am, then a chance of showers after 2am. Low around 69. Chance of precipitation is 80%.

    Low: 69 °F

    Showers

  • Monday

    Monday: A 30 percent chance of showers before 8am. Partly sunny, with a high near 82.

    High: 82 °F

    Chance
    Showers then
    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 67.

    Low: 67 °F

    Partly Cloudy

Detailed Forecast

Tonight
Partly cloudy, with a low around 68. West wind around 6 mph becoming light and variable in the evening.
Friday
Mostly sunny, with a high near 84. Light and variable wind becoming southwest 5 to 7 mph in the morning.
Friday Night
Partly cloudy, with a low around 65. Light and variable wind.
Saturday
Sunny, with a high near 82. Northeast wind around 7 mph.
Saturday Night
Partly cloudy, with a low around 66. South wind around 5 mph becoming calm in the evening.
Sunday
A 50 percent chance of showers after 2pm. Partly sunny, with a high near 81.
Sunday Night
A chance of showers before 8pm, then showers and possibly a thunderstorm between 8pm and 2am, then a chance of showers after 2am. Low around 69. Chance of precipitation is 80%.
Monday
A 30 percent chance of showers before 8am. Partly sunny, with a high near 82.
Monday Night
Partly cloudy, with a low around 67.
Tuesday
Sunny, with a high near 81.
Tuesday Night
Mostly clear, with a low around 68.
Wednesday
Sunny, with a high near 81.
Wednesday Night
Partly cloudy, with a low around 70.
Thursday
A 30 percent chance of showers. Mostly sunny, with a high near 83.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Sayville NY
 40.76°N 73.09°W (Elev. 49 ft)
Last Update:
8:32 pm EDT Aug 13, 2026
Forecast Valid:
8pm EDT Aug 13, 2026-6pm EDT Aug 20, 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