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

42°F

6°C

Humidity 53%
Wind Speed W 14 G 28 mph
Barometer 29.84 in (1010.7 mb)
Dewpoint 26°F (-3°C)
Visibility 10.00 mi
Wind Chill35°F (2°C)
Last update 11 Nov 8:56 pm EST
Extended Forecast for

Great River NY

  • Tonight

    Tonight: Increasing clouds, with a low around 35. Breezy, with a west wind 14 to 21 mph, with gusts as high as 32 mph.

    Low: 35 °F

    Mostly Clear
    and Breezy
    then Mostly
    Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 51. West wind 14 to 17 mph.

    High: 51 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 40. West wind 14 to 16 mph.

    Low: 40 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 53. West wind 15 to 17 mph.

    High: 53 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 37. West wind 10 to 16 mph.

    Low: 37 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 51.

    High: 51 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 31.

    Low: 31 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 48.

    High: 48 °F

    Sunny

  • Saturday Night

    Saturday Night: A 30 percent chance of rain after 1am. Mostly cloudy, with a low around 34.

    Low: 34 °F

    Partly Cloudy
    then Chance
    Rain

Detailed Forecast

Tonight
Increasing clouds, with a low around 35. Breezy, with a west wind 14 to 21 mph, with gusts as high as 32 mph.
Wednesday
Partly sunny, with a high near 51. West wind 14 to 17 mph.
Wednesday Night
Partly cloudy, with a low around 40. West wind 14 to 16 mph.
Thursday
Mostly sunny, with a high near 53. West wind 15 to 17 mph.
Thursday Night
Mostly clear, with a low around 37. West wind 10 to 16 mph.
Friday
Mostly sunny, with a high near 51.
Friday Night
Partly cloudy, with a low around 31.
Saturday
Sunny, with a high near 48.
Saturday Night
A 30 percent chance of rain after 1am. Mostly cloudy, with a low around 34.
Sunday
A 50 percent chance of rain. Mostly cloudy, with a high near 57.
Sunday Night
A 30 percent chance of rain. Mostly cloudy, with a low around 42.
Monday
Mostly sunny, with a high near 52.
Monday Night
Partly cloudy, with a low around 37.
Tuesday
Mostly sunny, with a high near 50.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Great River NY
 40.72°N 73.16°W (Elev. 13 ft)
Last Update:
1:09 pm EST Nov 11, 2025
Forecast Valid:
9pm EST Nov 11, 2025-6pm EST Nov 18, 2025
 
Forecast Discussion
 
Get as KML Get as XML

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