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.

Light Rain

77°F

25°C

Humidity 94%
Wind Speed S 6 mph
Barometer 30.05 in (1017.3 mb)
Dewpoint 75°F (24°C)
Visibility 10.00 mi
Heat Index78°F (26°C)
Last update 14 Jul 11:56 pm EDT
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Overnight

    Overnight: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 2am. Patchy fog after 4am. Otherwise, mostly cloudy, with a low around 74. South wind around 6 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 74 °F

    Showers
    Likely and
    Patchy Fog

  • Tuesday

    Tuesday: Showers likely and possibly a thunderstorm before 8am, then a chance of showers and thunderstorms, mainly between 8am and 11am. Patchy fog before 9am. Otherwise, mostly cloudy, then gradually becoming sunny, with a high near 83. Calm wind becoming south 5 to 8 mph in the afternoon. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 83 °F

    Showers
    Likely and
    Patchy Fog
    then Slight
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: Patchy fog after 4am. Otherwise, partly cloudy, with a low around 74. Southwest wind 5 to 7 mph.

    Low: 74 °F

    Partly Cloudy
    then Patchy
    Fog

  • Wednesday

    Wednesday: A slight chance of showers, with thunderstorms also possible after 2pm. Patchy fog before 8am. Otherwise, partly sunny, with a high near 88. Light southwest wind becoming south 5 to 10 mph in the morning. Chance of precipitation is 20%.

    High: 88 °F

    Slight Chance
    T-storms and
    Patchy Fog

  • Wednesday Night

    Wednesday Night: A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 76. Southwest wind 8 to 10 mph.

    Low: 76 °F

    Chance
    T-storms

  • Thursday

    Thursday: A chance of showers, with thunderstorms also possible after 2pm. Partly sunny, with a high near 89. Chance of precipitation is 30%.

    High: 89 °F

    Chance
    Showers then
    Chance
    T-storms

  • Thursday Night

    Thursday Night: A chance of thunderstorms before 8pm. Partly cloudy, with a low around 77. Chance of precipitation is 30%.

    Low: 77 °F

    Chance
    T-storms then
    Partly Cloudy

  • Friday

    Friday: A 30 percent chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 90.

    High: 90 °F

    Mostly Sunny
    then Chance
    T-storms

  • Friday Night

    Friday Night: A 30 percent chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 73.

    Low: 73 °F

    Chance
    T-storms then
    Partly Cloudy

Detailed Forecast

Overnight
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 2am. Patchy fog after 4am. Otherwise, mostly cloudy, with a low around 74. South wind around 6 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tuesday
Showers likely and possibly a thunderstorm before 8am, then a chance of showers and thunderstorms, mainly between 8am and 11am. Patchy fog before 9am. Otherwise, mostly cloudy, then gradually becoming sunny, with a high near 83. Calm wind becoming south 5 to 8 mph in the afternoon. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Tuesday Night
Patchy fog after 4am. Otherwise, partly cloudy, with a low around 74. Southwest wind 5 to 7 mph.
Wednesday
A slight chance of showers, with thunderstorms also possible after 2pm. Patchy fog before 8am. Otherwise, partly sunny, with a high near 88. Light southwest wind becoming south 5 to 10 mph in the morning. Chance of precipitation is 20%.
Wednesday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 76. Southwest wind 8 to 10 mph.
Thursday
A chance of showers, with thunderstorms also possible after 2pm. Partly sunny, with a high near 89. Chance of precipitation is 30%.
Thursday Night
A chance of thunderstorms before 8pm. Partly cloudy, with a low around 77. Chance of precipitation is 30%.
Friday
A 30 percent chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 90.
Friday Night
A 30 percent chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 73.
Saturday
Mostly sunny, with a high near 86.
Saturday Night
Partly cloudy, with a low around 72.
Sunday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 85.
Sunday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 73.
Monday
Mostly sunny, with a high near 86.
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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:
2:29 pm EDT Jul 14, 2025
Forecast Valid:
12am EDT Jul 15, 2025-6pm EDT Jul 21, 2025
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation