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.

Partly Cloudy

56°F

13°C

Humidity 57%
Wind Speed W 9 mph
Barometer 29.75 in (1007.4 mb)
Dewpoint 41°F (5°C)
Visibility 10.00 mi
Last update 8 Nov 4:56 pm EST
Extended Forecast for

Great River NY

  • Tonight

    Tonight: Mostly clear, with a low around 42. West wind 11 to 13 mph, with gusts as high as 23 mph.

    Low: 42 °F

    Mostly Clear

  • Monday

    Monday: Mostly cloudy, then gradually becoming sunny, with a high near 58. Northwest wind 13 to 17 mph, with gusts as high as 28 mph.

    High: 58 °F

    Decreasing
    Clouds

  • Monday Night

    Monday Night: Mostly clear, with a low around 39. Northwest wind 9 to 11 mph.

    Low: 39 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 60. West wind 9 to 14 mph.

    High: 60 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Clear, with a low around 42. West wind around 9 mph.

    Low: 42 °F

    Clear

  • Veterans Day

    Veterans Day: Sunny, with a high near 60.

    High: 60 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 43.

    Low: 43 °F

    Mostly Cloudy

  • Thursday

    Thursday: A 40 percent chance of rain after 1pm. Mostly cloudy, with a high near 57.

    High: 57 °F

    Mostly Cloudy
    then Chance
    Rain

  • Thursday Night

    Thursday Night: Rain. Low around 40. Breezy. Chance of precipitation is 80%.

    Low: 40 °F

    Rain and
    Breezy

Detailed Forecast

Tonight
Mostly clear, with a low around 42. West wind 11 to 13 mph, with gusts as high as 23 mph.
Monday
Mostly cloudy, then gradually becoming sunny, with a high near 58. Northwest wind 13 to 17 mph, with gusts as high as 28 mph.
Monday Night
Mostly clear, with a low around 39. Northwest wind 9 to 11 mph.
Tuesday
Sunny, with a high near 60. West wind 9 to 14 mph.
Tuesday Night
Clear, with a low around 42. West wind around 9 mph.
Veterans Day
Sunny, with a high near 60.
Wednesday Night
Mostly cloudy, with a low around 43.
Thursday
A 40 percent chance of rain after 1pm. Mostly cloudy, with a high near 57.
Thursday Night
Rain. Low around 40. Breezy. Chance of precipitation is 80%.
Friday
Rain. High near 49. Breezy. Chance of precipitation is 80%.
Friday Night
A 40 percent chance of rain. Mostly cloudy, with a low around 35. Breezy.
Saturday
A 30 percent chance of rain. Partly sunny, with a high near 47.
Saturday Night
Partly cloudy, with a low around 35.
Sunday
Mostly sunny, with a high near 48.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Great River NY
 40.72°N 73.16°W (Elev. 13 ft)
Last Update:
1:44 pm EST Nov 8, 2026
Forecast Valid:
5pm EST Nov 8, 2026-6pm EST Nov 15, 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