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

66°F

19°C

Humidity 47%
Wind Speed NW 12 mph
Barometer 29.89 in (1012.0 mb)
Dewpoint 45°F (7°C)
Visibility 10.00 mi
Last update 15 May 4:56 pm EDT
Extended Forecast for

Ronkonkoma NY

  • Tonight

    Tonight: Mostly cloudy, then gradually becoming clear, with a low around 52. Northwest wind 5 to 9 mph becoming calm in the evening.

    Low: 52 °F

    Decreasing
    Clouds

  • Saturday

    Saturday: Sunny, with a high near 73. South wind 7 to 12 mph increasing to 13 to 18 mph in the afternoon. Winds could gust as high as 28 mph.

    High: 73 °F

    Sunny

  • Saturday Night

    Saturday Night: Increasing clouds, with a low around 59. Southwest wind 13 to 17 mph.

    Low: 59 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Sunny, with a high near 82. West wind 9 to 15 mph.

    High: 82 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 59. Southwest wind 5 to 10 mph becoming light and variable in the evening.

    Low: 59 °F

    Partly Cloudy

  • Monday

    Monday: Sunny, with a high near 73.

    High: 73 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 58.

    Low: 58 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 81.

    High: 81 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 63.

    Low: 63 °F

    Mostly Clear

Detailed Forecast

Tonight
Mostly cloudy, then gradually becoming clear, with a low around 52. Northwest wind 5 to 9 mph becoming calm in the evening.
Saturday
Sunny, with a high near 73. South wind 7 to 12 mph increasing to 13 to 18 mph in the afternoon. Winds could gust as high as 28 mph.
Saturday Night
Increasing clouds, with a low around 59. Southwest wind 13 to 17 mph.
Sunday
Sunny, with a high near 82. West wind 9 to 15 mph.
Sunday Night
Partly cloudy, with a low around 59. Southwest wind 5 to 10 mph becoming light and variable in the evening.
Monday
Sunny, with a high near 73.
Monday Night
Mostly clear, with a low around 58.
Tuesday
Sunny, with a high near 81.
Tuesday Night
Mostly clear, with a low around 63.
Wednesday
A 30 percent chance of showers after 2pm. Mostly sunny, with a high near 79.
Wednesday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 59.
Thursday
A 40 percent chance of showers. Partly sunny, with a high near 69.
Thursday Night
Partly cloudy, with a low around 53.
Friday
Mostly sunny, with a high near 68.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Ronkonkoma NY
 40.81°N 73.11°W (Elev. 98 ft)
Last Update:
2:26 pm EDT May 15, 2026
Forecast Valid:
5pm EDT May 15, 2026-6pm EDT May 22, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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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