National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Mostly Cloudy

81°F

27°C

Humidity 57%
Wind Speed S 7 mph
Barometer 30.00 in (1015.6 mb)
Dewpoint 64°F (18°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 20 Aug 12:56 pm EDT
Extended Forecast for

5 Miles SSE Bayport NY

Flood Watch August 20, 02:00pm until August 21, 02:00am
Click here for hazard details and duration
Flood Watch

  • This Afternoon

    This Afternoon: A 30 percent chance of showers and thunderstorms after 5pm. Partly sunny, with a high near 81. South wind 6 to 9 mph.

    High: 81 °F

    Chance
    Showers

  • Tonight

    Tonight: A chance of showers and thunderstorms before 8pm, then showers and possibly a thunderstorm between 8pm and 2am, then showers likely after 2am. Low around 69. Northeast wind 8 to 16 mph. Chance of precipitation is 90%. New rainfall amounts between 1 and 2 inches possible.

    Low: 69 °F

    Showers

  • Friday

    Friday: A 40 percent chance of showers. Mostly cloudy, with a high near 76. Northeast wind 13 to 18 mph.

    High: 76 °F

    Chance
    Showers

  • Friday Night

    Friday Night: Showers likely after 2am. Mostly cloudy, with a low around 70. Northeast wind 11 to 13 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    Low: 70 °F

    Mostly Cloudy
    then Showers
    Likely

  • Saturday

    Saturday: Showers, with thunderstorms also possible after 2pm. High near 77. Northeast wind around 14 mph. Chance of precipitation is 80%. New rainfall amounts between three quarters and one inch possible.

    High: 77 °F

    Showers

  • Saturday Night

    Saturday Night: Showers likely. Mostly cloudy, with a low around 71. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    Low: 71 °F

    Showers
    Likely

  • Sunday

    Sunday: A 30 percent chance of showers. Partly sunny, with a high near 79.

    High: 79 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 71.

    Low: 71 °F

    Partly Cloudy

  • Monday

    Monday: Sunny, with a high near 79.

    High: 79 °F

    Sunny

Detailed Forecast

This Afternoon
A 30 percent chance of showers and thunderstorms after 5pm. Partly sunny, with a high near 81. South wind 6 to 9 mph.
Tonight
A chance of showers and thunderstorms before 8pm, then showers and possibly a thunderstorm between 8pm and 2am, then showers likely after 2am. Low around 69. Northeast wind 8 to 16 mph. Chance of precipitation is 90%. New rainfall amounts between 1 and 2 inches possible.
Friday
A 40 percent chance of showers. Mostly cloudy, with a high near 76. Northeast wind 13 to 18 mph.
Friday Night
Showers likely after 2am. Mostly cloudy, with a low around 70. Northeast wind 11 to 13 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Saturday
Showers, with thunderstorms also possible after 2pm. High near 77. Northeast wind around 14 mph. Chance of precipitation is 80%. New rainfall amounts between three quarters and one inch possible.
Saturday Night
Showers likely. Mostly cloudy, with a low around 71. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Sunday
A 30 percent chance of showers. Partly sunny, with a high near 79.
Sunday Night
Partly cloudy, with a low around 71.
Monday
Sunny, with a high near 79.
Monday Night
Mostly clear, with a low around 69.
Tuesday
Sunny, with a high near 78.
Tuesday Night
Mostly clear, with a low around 70.
Wednesday
Mostly sunny, with a high near 78.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
5 Miles SSE Bayport NY
 40.68°N 73.02°W (Elev. 0 ft)
Last Update:
12:06 pm EDT Aug 20, 2026
Forecast Valid:
1pm EDT Aug 20, 2026-6pm EDT Aug 26, 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