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.

Mostly Cloudy

33°F

1°C

Humidity 92%
Wind Speed W 9 mph
Barometer 29.93 in (1013.6 mb)
Dewpoint 31°F (-1°C)
Visibility 9.00 mi
Wind Chill25°F (-4°C)
Last update 12 Mar 8:56 pm EDT
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Tonight

    Tonight: A 20 percent chance of snow before 11pm. Mostly cloudy, then gradually becoming clear, with a low around 29. West wind 11 to 14 mph.

    Low: 29 °F

    Slight Chance
    Snow then
    Mostly Clear

  • Friday

    Friday: Increasing clouds, with a high near 46. Wind chill values between 25 and 35 early. West wind 5 to 10 mph becoming south 12 to 17 mph in the afternoon.

    High: 46 °F

    Increasing
    Clouds

  • Friday Night

    Friday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 36. South wind 15 to 17 mph, with gusts as high as 33 mph.

    Low: 36 °F

    Decreasing
    Clouds

  • Saturday

    Saturday: Sunny, with a high near 50. Breezy, with a west wind 18 to 21 mph, with gusts as high as 34 mph.

    High: 50 °F

    Sunny and
    Breezy

  • Saturday Night

    Saturday Night: Increasing clouds, with a low around 31. Northwest wind 6 to 11 mph becoming light after midnight.

    Low: 31 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Mostly cloudy, with a high near 48.

    High: 48 °F

    Mostly Cloudy

  • Sunday Night

    Sunday Night: Rain, mainly after 2am. Low around 40. Chance of precipitation is 80%.

    Low: 40 °F

    Chance Rain
    then Rain

  • Monday

    Monday: Rain and possibly a thunderstorm. High near 57. Breezy. Chance of precipitation is 100%.

    High: 57 °F

    Rain and
    Breezy

  • Monday Night

    Monday Night: Rain, mainly before 2am. Low around 35. Breezy. Chance of precipitation is 80%.

    Low: 35 °F

    Rain and
    Breezy

Detailed Forecast

Tonight
A 20 percent chance of snow before 11pm. Mostly cloudy, then gradually becoming clear, with a low around 29. West wind 11 to 14 mph.
Friday
Increasing clouds, with a high near 46. Wind chill values between 25 and 35 early. West wind 5 to 10 mph becoming south 12 to 17 mph in the afternoon.
Friday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 36. South wind 15 to 17 mph, with gusts as high as 33 mph.
Saturday
Sunny, with a high near 50. Breezy, with a west wind 18 to 21 mph, with gusts as high as 34 mph.
Saturday Night
Increasing clouds, with a low around 31. Northwest wind 6 to 11 mph becoming light after midnight.
Sunday
Mostly cloudy, with a high near 48.
Sunday Night
Rain, mainly after 2am. Low around 40. Chance of precipitation is 80%.
Monday
Rain and possibly a thunderstorm. High near 57. Breezy. Chance of precipitation is 100%.
Monday Night
Rain, mainly before 2am. Low around 35. Breezy. Chance of precipitation is 80%.
Tuesday
A 30 percent chance of rain before 8am. Mostly sunny, with a high near 44.
Tuesday Night
Partly cloudy, with a low around 24.
Wednesday
Sunny, with a high near 39.
Wednesday Night
Partly cloudy, with a low around 28.
Thursday
Mostly sunny, with a high near 44.
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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:
6:03 pm EDT Mar 12, 2026
Forecast Valid:
9pm EDT Mar 12, 2026-6pm EDT Mar 19, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation