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

45°F

7°C

Humidity 44%
Wind Speed S 10 mph
Barometer 29.98 in
Dewpoint 24°F (-4°C)
Visibility 10.00 mi
Wind Chill40°F (4°C)
Last update 13 Jan 12:56 pm EST
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • This Afternoon

    This Afternoon: Mostly sunny, with a high near 44. South wind around 9 mph.

    High: 44 °F

    Mostly Sunny

  • Tonight

    Tonight: A 20 percent chance of rain after 4am. Mostly cloudy, with a low around 38. Southwest wind 8 to 10 mph, with gusts as high as 23 mph.

    Low: 38 °F

    Mostly Cloudy
    then Slight
    Chance Rain

  • Wednesday

    Wednesday: A 20 percent chance of rain before 10am. Mostly cloudy, with a high near 46. Southwest wind 6 to 9 mph.

    High: 46 °F

    Slight Chance
    Rain then
    Mostly Cloudy

  • Wednesday Night

    Wednesday Night: A 40 percent chance of rain, mainly after 1am. Cloudy, with a low around 29. Calm wind becoming southwest around 6 mph after midnight.

    Low: 29 °F

    Chance Rain

  • Thursday

    Thursday: Cloudy, then gradually becoming mostly sunny, with a temperature rising to near 35 by 10am, then falling to around 28 during the remainder of the day. West wind 8 to 14 mph, with gusts as high as 24 mph.

    High: 35 °F⇓

    Decreasing
    Clouds

  • Thursday Night

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

    Low: 16 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 35.

    High: 35 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 27.

    Low: 27 °F

    Mostly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 42.

    High: 42 °F

    Partly Sunny

Detailed Forecast

This Afternoon
Mostly sunny, with a high near 44. South wind around 9 mph.
Tonight
A 20 percent chance of rain after 4am. Mostly cloudy, with a low around 38. Southwest wind 8 to 10 mph, with gusts as high as 23 mph.
Wednesday
A 20 percent chance of rain before 10am. Mostly cloudy, with a high near 46. Southwest wind 6 to 9 mph.
Wednesday Night
A 40 percent chance of rain, mainly after 1am. Cloudy, with a low around 29. Calm wind becoming southwest around 6 mph after midnight.
Thursday
Cloudy, then gradually becoming mostly sunny, with a temperature rising to near 35 by 10am, then falling to around 28 during the remainder of the day. West wind 8 to 14 mph, with gusts as high as 24 mph.
Thursday Night
Partly cloudy, with a low around 16.
Friday
Mostly sunny, with a high near 35.
Friday Night
Mostly cloudy, with a low around 27.
Saturday
Partly sunny, with a high near 42.
Saturday Night
Mostly cloudy, with a low around 26.
Sunday
Partly sunny, with a high near 33.
Sunday Night
Partly cloudy, with a low around 20.
M.L.King Day
Mostly sunny, with a high near 31.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islip, Long Island Mac Arthur Airport NY
 40.8°N 73.09°W (Elev. 98 ft)
Last Update:
12:35 pm EST Jan 13, 2026
Forecast Valid:
1pm EST Jan 13, 2026-6pm EST Jan 19, 2026
 
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Additional Resources

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Chance of Precipitation