National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Heat Wave Continues in the West; Critical Fire Weather Conditions in the High Plains

An anomalously early heat wave will continue to intensify and expand across the West and Southwest as the week progresses. Numerous daily and potentially monthly record highs are expected to be broken. Critical fire weather conditions will continue over the next couple of days across portions of the High Plains as gusty winds and dry conditions persist. Read More >

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

A Few Clouds

26°F

-3°C

Humidity 42%
Wind Speed NW 7 mph
Barometer 30.31 in (1026.3 mb)
Dewpoint 6°F (-14°C)
Visibility 10.00 mi
Wind Chill18°F (-8°C)
Last update 18 Mar 5:56 am EDT
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Today

    Today: Increasing clouds, with a high near 36. Wind chill values between 20 and 30. North wind 5 to 8 mph becoming calm in the afternoon.

    High: 36 °F

    Increasing
    Clouds

  • Tonight

    Tonight: Increasing clouds, with a low around 27. Calm wind.

    Low: 27 °F

    Increasing
    Clouds

  • Thursday

    Thursday: Mostly sunny, with a high near 42. Calm wind becoming southeast around 6 mph in the afternoon.

    High: 42 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 33. Calm wind.

    Low: 33 °F

    Mostly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 50. Calm wind becoming southwest 5 to 7 mph in the afternoon.

    High: 50 °F

    Mostly Sunny

  • Friday Night

    Friday Night: A 50 percent chance of rain. Mostly cloudy, with a low around 39.

    Low: 39 °F

    Chance Rain

  • Saturday

    Saturday: A 40 percent chance of rain before 2pm. Partly sunny, with a high near 51.

    High: 51 °F

    Chance Rain

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 39.

    Low: 39 °F

    Mostly Cloudy

  • Sunday

    Sunday: A 40 percent chance of rain after 8am. Mostly cloudy, with a high near 53.

    High: 53 °F

    Chance Rain

Detailed Forecast

Today
Increasing clouds, with a high near 36. Wind chill values between 20 and 30. North wind 5 to 8 mph becoming calm in the afternoon.
Tonight
Increasing clouds, with a low around 27. Calm wind.
Thursday
Mostly sunny, with a high near 42. Calm wind becoming southeast around 6 mph in the afternoon.
Thursday Night
Mostly cloudy, with a low around 33. Calm wind.
Friday
Mostly sunny, with a high near 50. Calm wind becoming southwest 5 to 7 mph in the afternoon.
Friday Night
A 50 percent chance of rain. Mostly cloudy, with a low around 39.
Saturday
A 40 percent chance of rain before 2pm. Partly sunny, with a high near 51.
Saturday Night
Mostly cloudy, with a low around 39.
Sunday
A 40 percent chance of rain after 8am. Mostly cloudy, with a high near 53.
Sunday Night
A chance of rain before 2am, then a chance of rain and snow. Mostly cloudy, with a low around 37. Chance of precipitation is 30%.
Monday
A 30 percent chance of snow. Mostly sunny, with a high near 49.
Monday Night
Mostly clear, with a low around 29.
Tuesday
Mostly sunny, with a high near 42.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Islip, Long Island Mac Arthur Airport NY
 40.78°N 73.09°W (Elev. 49 ft)
Last Update:
6:17 am EDT Mar 18, 2026
Forecast Valid:
6am EDT Mar 18, 2026-6pm EDT Mar 24, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation