Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

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

Mostly Cloudy

76°F

24°C

Humidity 88%
Wind Speed SE 10 mph
Barometer 30.08 in (1018.6 mb)
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index76°F (24°C)
Last update 13 Jul 8:56 pm EDT
Detailed forecast for

Northwest Suffolk

Tonight
Mostly cloudy. Patchy fog after midnight. Lows in the lower 70s. Southeast winds 5 to 10 mph.
Monday
Partly sunny. Patchy fog in the morning. Patchy drizzle in the morning, then a slight chance of showers and thunderstorms in the afternoon. Humid with highs in the lower 80s. South winds 5 to 10 mph. Chance of rain 20 percent.
Monday 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.
Tuesday
Mostly cloudy with a chance of showers and thunderstorms in the morning, then partly sunny with a chance of showers with a slight chance of thunderstorms in the afternoon. Humid with highs in the mid 80s. South winds 5 to 10 mph. Chance of rain 50 percent.
Tuesday Night
Partly cloudy. A chance of showers, mainly in the evening. Humid with lows in the lower 70s. South winds 5 to 10 mph. Chance of rain 40 percent.
Wednesday
Partly sunny. Highs in the upper 80s. Heat index values in the upper 90s.
Wednesday Night
Mostly cloudy with a chance of showers. Lows in the mid 70s. Chance of rain 30 percent.
Thursday
Partly sunny. A chance of showers and thunderstorms in the afternoon. Highs in the lower 90s. Chance of rain 40 percent. Heat index values up to 105.
Thursday Night
Mostly cloudy. A chance of showers and thunderstorms in the evening. Lows in the mid 70s. Chance of rain 40 percent.
Friday
Partly sunny. A chance of showers in the afternoon. Highs in the lower 90s. Chance of rain 30 percent. Heat index values up to 105.
Friday Night
Mostly cloudy in the evening, then becoming partly cloudy. A chance of showers. Lows in the lower 70s. Chance of rain 30 percent.
Saturday
Partly sunny. A chance of showers in the afternoon. Highs in the upper 80s. Chance of rain 30 percent.
Saturday Night
Mostly cloudy with a 30 percent chance of showers. Lows in the lower 70s.
Sunday
Partly sunny. A chance of showers in the morning. Highs in the mid 80s. Chance of rain 30 percent.



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548 PM EDT Sun Jul 13 2025
 
 

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