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 73%
Wind Speed Calm
Barometer 30.10 in (1019.3 mb)
Dewpoint 59°F (15°C)
Visibility 10.00 mi
Last update 18 Jul 11:56 pm EDT
Detailed forecast for

Southwest Suffolk

This Afternoon
Partly sunny. Highs in the lower 80s. Northwest winds 5 to 10 mph with gusts up to 20 mph.
Tonight
Partly cloudy in the evening, then clearing. Lows in the mid 60s. Northwest winds around 5 mph.
Saturday
Mostly sunny. Highs in the lower 80s. East winds around 5 mph, becoming south in the afternoon.
Saturday Night
Mostly cloudy with a chance of showers and thunderstorms. Humid with lows in the lower 70s. South winds 5 to 10 mph. Chance of rain 50 percent.
Sunday
Partly sunny with a chance of showers and thunderstorms. Humid with highs in the mid 80s. Southwest winds 5 to 10 mph. Gusts up to 20 mph in the afternoon. Chance of rain 50 percent. Heat index values in the mid 90s.
Sunday Night
Partly cloudy with a chance of showers and thunderstorms in the evening, then mostly clear after midnight. Lows around 70. Chance of rain 50 percent.
Monday
Sunny. Highs in the mid 80s.
Monday Night
Mostly clear in the evening, then becoming partly cloudy. Lows in the mid 60s.
Tuesday
Sunny. Highs in the lower 80s.
Tuesday Night
Mostly clear in the evening, then becoming partly cloudy. Lows in the upper 60s.
Wednesday
Mostly sunny. Highs in the mid 80s.
Wednesday Night
Partly cloudy. Lows in the lower 70s.
Thursday
Partly sunny. Highs in the mid 80s. Heat index values in the upper 90s.
Thursday Night
Mostly cloudy with a chance of showers. Lows in the mid 70s. Chance of rain 30 percent.
Friday
Mostly sunny. Highs in the upper 80s. Heat index values up to 100.



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142 PM EDT Fri Jul 18 2025
 
 

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