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.

Mostly Cloudy

79°F

26°C

Humidity 42%
Wind Speed SW 13 mph
Barometer 30.15 in (1021.0 mb)
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 4 Oct 3:56 pm EDT
Extended Forecast for

Ronkonkoma NY

  • Tonight

    Tonight: Patchy fog after midnight. Otherwise, mostly clear, with a low around 58. Southwest wind 5 to 9 mph becoming calm in the evening.

    Low: 58 °F

    Mostly Clear
    then Patchy
    Fog

  • Sunday

    Sunday: Sunny, with a high near 82. Calm wind becoming south 5 to 8 mph in the afternoon.

    High: 82 °F

    Sunny

  • Sunday Night

    Sunday Night: Patchy fog after 5am. Otherwise, clear, with a low around 57. Southwest wind around 6 mph.

    Low: 57 °F

    Clear then
    Patchy Fog

  • Monday

    Monday: Patchy fog before 8am. Otherwise, sunny, with a high near 79. Southwest wind 5 to 11 mph.

    High: 79 °F

    Patchy Fog
    then Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 60. South wind 8 to 10 mph.

    Low: 60 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 79.

    High: 79 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Showers likely, mainly after 2am. Mostly cloudy, with a low around 62. Chance of precipitation is 70%.

    Low: 62 °F

    Chance
    Showers then
    Showers
    Likely

  • Wednesday

    Wednesday: Showers likely, mainly before 2pm. Mostly cloudy, with a high near 73. Chance of precipitation is 60%.

    High: 73 °F

    Showers
    Likely

  • Wednesday Night

    Wednesday Night: A 30 percent chance of showers before 8pm. Partly cloudy, with a low around 50.

    Low: 50 °F

    Chance
    Showers then
    Partly Cloudy

Detailed Forecast

Tonight
Patchy fog after midnight. Otherwise, mostly clear, with a low around 58. Southwest wind 5 to 9 mph becoming calm in the evening.
Sunday
Sunny, with a high near 82. Calm wind becoming south 5 to 8 mph in the afternoon.
Sunday Night
Patchy fog after 5am. Otherwise, clear, with a low around 57. Southwest wind around 6 mph.
Monday
Patchy fog before 8am. Otherwise, sunny, with a high near 79. Southwest wind 5 to 11 mph.
Monday Night
Mostly clear, with a low around 60. South wind 8 to 10 mph.
Tuesday
Mostly sunny, with a high near 79.
Tuesday Night
Showers likely, mainly after 2am. Mostly cloudy, with a low around 62. Chance of precipitation is 70%.
Wednesday
Showers likely, mainly before 2pm. Mostly cloudy, with a high near 73. Chance of precipitation is 60%.
Wednesday Night
A 30 percent chance of showers before 8pm. Partly cloudy, with a low around 50.
Thursday
Sunny, with a high near 66.
Thursday Night
Mostly clear, with a low around 50.
Friday
Mostly sunny, with a high near 68.
Friday Night
Partly cloudy, with a low around 54.
Saturday
Mostly sunny, with a high near 72.
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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:
2:02 pm EDT Oct 4, 2025
Forecast Valid:
4pm EDT Oct 4, 2025-6pm EDT Oct 11, 2025
 
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