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.

Fair

34°F

1°C

Humidity 48%
Wind Speed SW 7 mph
Barometer 30.08 in (1018.7 mb)
Dewpoint 16°F (-9°C)
Visibility 10.00 mi
Wind Chill28°F (-2°C)
Last update 17 Jan 12:56 am EST
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Overnight

    Overnight: Mostly cloudy, with a low around 28. South wind 7 to 9 mph.

    Low: 28 °F

    Mostly Cloudy

  • Saturday

    Saturday: A slight chance of snow before 9am, then rain likely. Mostly cloudy, with a high near 43. Southwest wind 8 to 14 mph. Chance of precipitation is 70%. Little or no snow accumulation expected.

    High: 43 °F

    Chance
    Rain/Snow
    then Rain
    Likely

  • Saturday Night

    Saturday Night: A chance of rain before 7pm, then a chance of rain and snow after 4am. Increasing clouds, with a low around 31. West wind 5 to 7 mph becoming calm in the evening. Chance of precipitation is 30%.

    Low: 31 °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 37. Calm wind becoming west 5 to 8 mph in the morning. Chance of precipitation is 70%. New snow accumulation of 1 to 2 inches possible.

    High: 37 °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 24. Northwest wind 6 to 8 mph.

    Low: 24 °F

    Chance Snow

  • M.L.King Day

    M.L.King Day: Mostly sunny, with a high near 36.

    High: 36 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 17.

    Low: 17 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 26.

    High: 26 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 14.

    Low: 14 °F

    Mostly Clear

Detailed Forecast

Overnight
Mostly cloudy, with a low around 28. South wind 7 to 9 mph.
Saturday
A slight chance of snow before 9am, then rain likely. Mostly cloudy, with a high near 43. Southwest wind 8 to 14 mph. Chance of precipitation is 70%. Little or no snow accumulation expected.
Saturday Night
A chance of rain before 7pm, then a chance of rain and snow after 4am. Increasing clouds, with a low around 31. West wind 5 to 7 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 37. Calm wind becoming west 5 to 8 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 24. Northwest wind 6 to 8 mph.
M.L.King Day
Mostly sunny, with a high near 36.
Monday Night
Partly cloudy, with a low around 17.
Tuesday
Sunny, with a high near 26.
Tuesday Night
Mostly clear, with a low around 14.
Wednesday
Mostly sunny, with a high near 36.
Wednesday Night
Mostly cloudy, with a low around 29.
Thursday
Partly sunny, with a high near 41.
Thursday Night
Mostly cloudy, with a low around 24.
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
 40.81°N 73.11°W (Elev. 98 ft)
Last Update:
12:59 am EST Jan 17, 2026
Forecast Valid:
1am EST Jan 17, 2026-6pm EST Jan 23, 2026
 
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Additional Resources

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