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.

Overcast

39°F

4°C

Humidity 82%
Wind Speed E 8 mph
Barometer 29.83 in (1010.2 mb)
Dewpoint 34°F (1°C)
Visibility 9.00 mi
Wind Chill33°F (1°C)
Last update 6 Jan 5:56 pm EST
Extended Forecast for

North Great River NY

  • Tonight

    Tonight: A 40 percent chance of rain, mainly between 7pm and 4am. Patchy fog after 10pm. Otherwise, cloudy, with a steady temperature around 39. Calm wind.

    Low: 39 °F

    Chance Rain
    and Patchy
    Fog

  • Wednesday

    Wednesday: Areas of fog before 7am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 47. Light west wind increasing to 6 to 11 mph in the morning. Winds could gust as high as 25 mph.

    High: 47 °F

    Areas Fog
    then Mostly
    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 31. Northwest wind 3 to 6 mph.

    Low: 31 °F

    Mostly Clear

  • Thursday

    Thursday: Mostly sunny, with a high near 44. Calm wind becoming west around 6 mph.

    High: 44 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 34. Calm wind.

    Low: 34 °F

    Mostly Cloudy

  • Friday

    Friday: Rain likely, mainly after 1pm. Cloudy, with a high near 50. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 50 °F

    Rain Likely

  • Friday Night

    Friday Night: A 50 percent chance of rain. Cloudy, with a low around 40.

    Low: 40 °F

    Chance Rain

  • Saturday

    Saturday: Rain. High near 49. Chance of precipitation is 80%.

    High: 49 °F

    Rain

  • Saturday Night

    Saturday Night: Rain, mainly before 1am. Low around 36. Chance of precipitation is 80%.

    Low: 36 °F

    Rain

Detailed Forecast

Tonight
A 40 percent chance of rain, mainly between 7pm and 4am. Patchy fog after 10pm. Otherwise, cloudy, with a steady temperature around 39. Calm wind.
Wednesday
Areas of fog before 7am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 47. Light west wind increasing to 6 to 11 mph in the morning. Winds could gust as high as 25 mph.
Wednesday Night
Mostly clear, with a low around 31. Northwest wind 3 to 6 mph.
Thursday
Mostly sunny, with a high near 44. Calm wind becoming west around 6 mph.
Thursday Night
Mostly cloudy, with a low around 34. Calm wind.
Friday
Rain likely, mainly after 1pm. Cloudy, with a high near 50. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Friday Night
A 50 percent chance of rain. Cloudy, with a low around 40.
Saturday
Rain. High near 49. Chance of precipitation is 80%.
Saturday Night
Rain, mainly before 1am. Low around 36. Chance of precipitation is 80%.
Sunday
A 40 percent chance of rain. Mostly cloudy, with a high near 47.
Sunday Night
Partly cloudy, with a low around 29.
Monday
Mostly sunny, with a high near 41.
Monday Night
Partly cloudy, with a low around 30.
Tuesday
Mostly sunny, with a high near 43.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
North Great River NY
 40.77°N 73.15°W (Elev. 30 ft)
Last Update:
1:40 pm EST Jan 6, 2026
Forecast Valid:
6pm EST Jan 6, 2026-6pm EST Jan 13, 2026
 
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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