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

82°F

28°C

Humidity 60%
Wind Speed SW 14 mph
Barometer 29.93 in (1013.3 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Heat Index84°F (29°C)
Last update 31 Jul 2:56 pm EDT
Extended Forecast for

Islip NYSimilar City Names

  • This Afternoon

    This Afternoon: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 82. Southwest wind around 8 mph.

    High: 82 °F

    Slight Chance
    T-storms

  • Tonight

    Tonight: Mostly clear, with a low around 69. Southwest wind 5 to 7 mph.

    Low: 69 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 84. South wind 6 to 11 mph.

    High: 84 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 70. South wind 5 to 9 mph.

    Low: 70 °F

    Mostly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 81. South wind 8 to 14 mph.

    High: 81 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Showers, mainly after 2am. Steady temperature around 75. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 75 °F

    Chance
    Showers then
    Showers

  • Monday

    Monday: Showers, with thunderstorms also possible after 2pm. Some of the storms could produce heavy rainfall. High near 81. Chance of precipitation is 80%.

    High: 81 °F

    Heavy Rain

  • Monday Night

    Monday Night: Showers likely and possibly a thunderstorm. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 69. Chance of precipitation is 60%.

    Low: 69 °F

    Heavy Rain

  • Tuesday

    Tuesday: Showers likely, mainly before 8am. Partly sunny, with a high near 82. Chance of precipitation is 60%.

    High: 82 °F

    Showers
    Likely

Detailed Forecast

This Afternoon
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 82. Southwest wind around 8 mph.
Tonight
Mostly clear, with a low around 69. Southwest wind 5 to 7 mph.
Saturday
Mostly sunny, with a high near 84. South wind 6 to 11 mph.
Saturday Night
Mostly cloudy, with a low around 70. South wind 5 to 9 mph.
Sunday
Partly sunny, with a high near 81. South wind 8 to 14 mph.
Sunday Night
Showers, mainly after 2am. Steady temperature around 75. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Monday
Showers, with thunderstorms also possible after 2pm. Some of the storms could produce heavy rainfall. High near 81. Chance of precipitation is 80%.
Monday Night
Showers likely and possibly a thunderstorm. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 69. Chance of precipitation is 60%.
Tuesday
Showers likely, mainly before 8am. Partly sunny, with a high near 82. Chance of precipitation is 60%.
Tuesday Night
A 30 percent chance of showers after 2am. Mostly cloudy, with a low around 69.
Wednesday
A 30 percent chance of showers. Mostly sunny, with a high near 82.
Wednesday Night
A 30 percent chance of showers. Partly cloudy, with a low around 71.
Thursday
A 30 percent chance of showers. Mostly sunny, with a high near 83.
Thursday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 71.
Friday
A chance of showers. Mostly sunny, with a high near 84.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Islip NYSimilar City Names
 40.73°N 73.22°W (Elev. 7 ft)
Last Update:
3:15 pm EDT Jul 31, 2026
Forecast Valid:
3pm EDT Jul 31, 2026-6pm EDT Aug 7, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation