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.

Overcast

64°F

18°C

Humidity 90%
Wind Speed E 3 mph
Barometer 30.05 in (1017.5 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Last update 17 Jun 1:56 am EDT
Extended Forecast for

Ronkonkoma NY

  • Overnight

    Overnight: A slight chance of drizzle or light rain. Patchy fog. Otherwise, cloudy, with a low around 64. East wind around 5 mph. Chance of precipitation is 20%.

    Low: 64 °F

    Slight Chance
    Light Rain
    and Patchy
    Fog

  • Tuesday

    Tuesday: A 30 percent chance of showers, mainly after noon. Patchy fog before noon. Otherwise, cloudy, with a high near 71. East wind 6 to 8 mph.

    High: 71 °F

    Chance
    Showers and
    Patchy Fog

  • Tuesday Night

    Tuesday Night: A chance of showers, with thunderstorms also possible after 2am. Areas of fog. Otherwise, cloudy, with a low around 65. Southeast wind around 5 mph. Chance of precipitation is 40%.

    Low: 65 °F

    Chance
    Showers and
    Areas Fog

  • Wednesday

    Wednesday: A chance of showers, with thunderstorms also possible after 5pm. Mostly cloudy, with a high near 79. South wind 5 to 10 mph. Chance of precipitation is 40%.

    High: 79 °F

    Slight Chance
    Showers then
    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms before 11pm, then a chance of showers between 11pm and 2am. Mostly cloudy, with a low around 68. South wind around 7 mph. Chance of precipitation is 40%.

    Low: 68 °F

    Chance
    T-storms then
    Chance
    Showers

  • Juneteenth

    Juneteenth: A 30 percent chance of showers after 2pm. Mostly sunny, with a high near 85.

    High: 85 °F

    Mostly Sunny
    then Chance
    Showers

  • Thursday Night

    Thursday Night: A 30 percent chance of showers before 2am. Partly cloudy, with a low around 67.

    Low: 67 °F

    Chance
    Showers

  • Friday

    Friday: Sunny, with a high near 83.

    High: 83 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 65.

    Low: 65 °F

    Mostly Clear

Detailed Forecast

Overnight
A slight chance of drizzle or light rain. Patchy fog. Otherwise, cloudy, with a low around 64. East wind around 5 mph. Chance of precipitation is 20%.
Tuesday
A 30 percent chance of showers, mainly after noon. Patchy fog before noon. Otherwise, cloudy, with a high near 71. East wind 6 to 8 mph.
Tuesday Night
A chance of showers, with thunderstorms also possible after 2am. Areas of fog. Otherwise, cloudy, with a low around 65. Southeast wind around 5 mph. Chance of precipitation is 40%.
Wednesday
A chance of showers, with thunderstorms also possible after 5pm. Mostly cloudy, with a high near 79. South wind 5 to 10 mph. Chance of precipitation is 40%.
Wednesday Night
A chance of showers and thunderstorms before 11pm, then a chance of showers between 11pm and 2am. Mostly cloudy, with a low around 68. South wind around 7 mph. Chance of precipitation is 40%.
Juneteenth
A 30 percent chance of showers after 2pm. Mostly sunny, with a high near 85.
Thursday Night
A 30 percent chance of showers before 2am. Partly cloudy, with a low around 67.
Friday
Sunny, with a high near 83.
Friday Night
Mostly clear, with a low around 65.
Saturday
Sunny, with a high near 82.
Saturday Night
Mostly cloudy, with a low around 67.
Sunday
Partly sunny, with a high near 84.
Sunday Night
Partly cloudy, with a low around 70.
Monday
Mostly sunny, with a high near 86.
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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:
11:55 pm EDT Jun 16, 2025
Forecast Valid:
2am EDT Jun 17, 2025-6pm EDT Jun 23, 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