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Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Light Rain

40°F

4°C

Humidity 86%
Wind Speed NW 16 G 26 mph
Barometer 29.63 in (1003.3 mb)
Dewpoint 36°F (2°C)
Visibility 10.00 mi
Wind Chill32°F (0°C)
Last update 2 Dec 10:56 pm EST
Extended Forecast for

Mount Sinai NY

  • Tonight

    Tonight: Cloudy, then gradually becoming partly cloudy, with a low around 31. Wind chill values between 25 and 30. Northwest wind 13 to 15 mph.

    Low: 31 °F

    Decreasing
    Clouds

  • Wednesday

    Wednesday: Sunny, with a high near 40. Wind chill values between 25 and 35. Northwest wind 6 to 10 mph.

    High: 40 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 31. West wind 5 to 10 mph.

    Low: 31 °F

    Mostly Clear

  • Thursday

    Thursday: Partly sunny, with a high near 41. West wind 10 to 17 mph, with gusts as high as 29 mph.

    High: 41 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 19. Northwest wind 8 to 18 mph, with gusts as high as 30 mph.

    Low: 19 °F

    Mostly Clear

  • Friday

    Friday: Increasing clouds, with a high near 35.

    High: 35 °F

    Increasing
    Clouds

  • Friday Night

    Friday Night: A chance of rain and snow before 1am, then a chance of snow. Mostly cloudy, with a low around 28. Chance of precipitation is 40%.

    Low: 28 °F

    Chance
    Rain/Snow

  • Saturday

    Saturday: A 30 percent chance of rain before 1pm. Partly sunny, with a high near 41.

    High: 41 °F

    Chance Rain

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 30.

    Low: 30 °F

    Partly Cloudy

Detailed Forecast

Tonight
Cloudy, then gradually becoming partly cloudy, with a low around 31. Wind chill values between 25 and 30. Northwest wind 13 to 15 mph.
Wednesday
Sunny, with a high near 40. Wind chill values between 25 and 35. Northwest wind 6 to 10 mph.
Wednesday Night
Mostly clear, with a low around 31. West wind 5 to 10 mph.
Thursday
Partly sunny, with a high near 41. West wind 10 to 17 mph, with gusts as high as 29 mph.
Thursday Night
Mostly clear, with a low around 19. Northwest wind 8 to 18 mph, with gusts as high as 30 mph.
Friday
Increasing clouds, with a high near 35.
Friday Night
A chance of rain and snow before 1am, then a chance of snow. Mostly cloudy, with a low around 28. Chance of precipitation is 40%.
Saturday
A 30 percent chance of rain before 1pm. Partly sunny, with a high near 41.
Saturday Night
Partly cloudy, with a low around 30.
Sunday
Partly sunny, with a high near 38.
Sunday Night
Mostly cloudy, with a low around 23.
Monday
Mostly sunny, with a high near 32.
Monday Night
Partly cloudy, with a low around 21.
Tuesday
Partly sunny, with a high near 35.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Mount Sinai NY
 40.95°N 73.02°W (Elev. 56 ft)
Last Update:
5:30 pm EST Dec 2, 2025
Forecast Valid:
11pm EST Dec 2, 2025-6pm EST Dec 9, 2025
 
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Additional Resources

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Chance of Precipitation