Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79° N Lon: 73.1° W Elev: 98 ft.

A Few Clouds

68°F

20°C

Humidity 78%
Wind Speed SW 8 mph
Barometer 30.13 in (1020.1 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Last update 18 May 9:56 pm EDT
Detailed forecast for

Southwest Suffolk

Tonight
Mostly clear. Lows in the lower 60s. Southwest winds 10 to 15 mph.
Tuesday
Sunny. Highs in the lower 80s. Southwest winds 5 to 10 mph with gusts up to 20 mph, increasing to 15 to 20 mph with gusts up to 30 mph in the afternoon.
Tuesday Night
Mostly cloudy. Lows in the mid 60s. Southwest winds 15 to 20 mph with gusts up to 30 mph.
Wednesday
Partly sunny. A chance of showers and thunderstorms in the afternoon. Highs in the lower 80s. Southwest winds 10 to 15 mph with gusts up to 30 mph. Chance of rain 50 percent.
Wednesday Night
Mostly cloudy. Showers with a chance of thunderstorms in the evening, then a chance of showers after midnight. Some thunderstorms may produce gusty winds, small hail, and heavy rainfall in the evening. Lows in the upper 50s. Northwest winds 10 to 15 mph, becoming north after midnight. Chance of rain 80 percent.
Thursday
Partly sunny. Highs in the upper 60s.
Thursday Night
Partly cloudy. Lows in the lower 50s.
Friday
Partly sunny. Highs in the mid 60s.
Friday Night
Mostly cloudy. A chance of showers in the evening, then showers likely after midnight. Lows around 50. Chance of rain 60 percent.
Saturday
Showers likely. Highs in the lower 60s. Chance of rain 70 percent.
Saturday Night
Showers likely. Lows in the lower 50s. Chance of rain 70 percent.
Sunday
Mostly cloudy. Showers likely, mainly in the morning. Highs in the mid 60s. Chance of rain 70 percent.
Sunday Night
Mostly cloudy with a 40 percent chance of showers. Lows in the mid 50s.
Memorial Day
Mostly cloudy with a 40 percent chance of showers. Highs in the upper 60s.



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746 PM EDT Mon May 18 2026
 
 

Additional Resources

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