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

43°F

6°C

Humidity 43%
Wind Speed SW 8 mph
Barometer 30.05 in (1017.5 mb)
Dewpoint 22°F (-6°C)
Visibility 10.00 mi
Wind Chill38°F (3°C)
Last update 17 Jan 10:56 am EST
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Today

    Today: Rain likely, mainly between 1pm and 4pm. Mostly cloudy, with a temperature falling to around 38 by 5pm. Southwest wind 8 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.

    High: 43 °F⇓

    Rain Likely

  • Tonight

    Tonight: A chance of rain before 7pm, then a chance of rain and snow after 4am. Increasing clouds, with a low around 30. West wind around 5 mph becoming calm in the evening. Chance of precipitation is 30%.

    Low: 30 °F

    Chance Rain
    then Chance
    Rain/Snow

  • Sunday

    Sunday: Snow likely, possibly mixed with rain, becoming all snow after 4pm. Cloudy, with a high near 36. Calm wind becoming west around 6 mph in the morning. Chance of precipitation is 70%. New snow accumulation of 1 to 2 inches possible.

    High: 36 °F

    Rain/Snow
    Likely

  • Sunday Night

    Sunday Night: A 30 percent chance of snow before 1am. Cloudy during the early evening, then gradual clearing, with a low around 22. Northwest wind 3 to 6 mph.

    Low: 22 °F

    Chance Snow

  • M.L.King Day

    M.L.King Day: Mostly sunny, with a high near 34. West wind 7 to 14 mph, with gusts as high as 25 mph.

    High: 34 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 16.

    Low: 16 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 25.

    High: 25 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 15.

    Low: 15 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 36.

    High: 36 °F

    Mostly Sunny

Detailed Forecast

Today
Rain likely, mainly between 1pm and 4pm. Mostly cloudy, with a temperature falling to around 38 by 5pm. Southwest wind 8 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.
Tonight
A chance of rain before 7pm, then a chance of rain and snow after 4am. Increasing clouds, with a low around 30. West wind around 5 mph becoming calm in the evening. Chance of precipitation is 30%.
Sunday
Snow likely, possibly mixed with rain, becoming all snow after 4pm. Cloudy, with a high near 36. Calm wind becoming west around 6 mph in the morning. Chance of precipitation is 70%. New snow accumulation of 1 to 2 inches possible.
Sunday Night
A 30 percent chance of snow before 1am. Cloudy during the early evening, then gradual clearing, with a low around 22. Northwest wind 3 to 6 mph.
M.L.King Day
Mostly sunny, with a high near 34. West wind 7 to 14 mph, with gusts as high as 25 mph.
Monday Night
Partly cloudy, with a low around 16.
Tuesday
Sunny, with a high near 25.
Tuesday Night
Mostly clear, with a low around 15.
Wednesday
Mostly sunny, with a high near 36.
Wednesday Night
Mostly cloudy, with a low around 29.
Thursday
Partly sunny, with a high near 39.
Thursday Night
Mostly cloudy, with a low around 22.
Friday
Mostly sunny, with a high near 33.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Islip, Long Island Mac Arthur Airport NY
 40.8°N 73.09°W (Elev. 98 ft)
Last Update:
4:17 am EST Jan 17, 2026
Forecast Valid:
11am EST Jan 17, 2026-6pm EST Jan 23, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation