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Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
Mostly Cloudy
38°F
3°C
| Humidity | 62% |
| Wind Speed | W 9 mph |
| Barometer | 29.99 in (1015.4 mb) |
| Dewpoint | 26°F (-3°C) |
| Visibility | 10.00 mi |
| Wind Chill | 32°F (0°C) |
| Last update | 4 Dec 9:56 am EST |
Extended Forecast for
Port Jefferson NY
Today
High: 40 °F⇓
Mostly Cloudy
then
Decreasing
Clouds and
BreezyTonight
Low: 17 °F
Mostly Clear
and Blustery
then Mostly
ClearFriday
High: 35 °F
Sunny then
Slight Chance
Light SnowFriday Night
Low: 28 °F
Chance Light
SnowSaturday
High: 41 °F
Slight Chance
Light RainSaturday Night
Low: 29 °F
Partly Cloudy
Sunday
High: 41 °F
Partly Sunny
Sunday Night
Low: 22 °F
Mostly Cloudy
Monday
High: 30 °F
Mostly Sunny
Detailed Forecast
Today
Mostly cloudy, then gradually becoming sunny, with a temperature falling to around 36 by 5pm. Wind chill values between 25 and 30. Breezy, with a west wind 13 to 18 mph increasing to 19 to 24 mph in the afternoon. Winds could gust as high as 34 mph.
Tonight
Mostly clear, with a low around 17. Wind chill values between 5 and 10. Blustery, with a northwest wind 19 to 24 mph decreasing to 8 to 13 mph after midnight. Winds could gust as high as 34 mph.
Friday
A 20 percent chance of light snow after 4pm. Increasing clouds, with a high near 35. Wind chill values between 10 and 20. Light and variable wind becoming southeast around 6 mph in the afternoon.
Friday Night
A 40 percent chance of light snow, mainly after 7pm. Mostly cloudy, with a low around 28. Light and variable wind.
Saturday
A 20 percent chance of light rain before 1pm. Cloudy, then gradually becoming mostly sunny, with a high near 41. Light and variable wind becoming northwest 5 to 7 mph in the morning.
Saturday Night
Partly cloudy, with a low around 29.
Sunday
Partly sunny, with a high near 41.
Sunday Night
Mostly cloudy, with a low around 22.
Monday
Mostly sunny, with a high near 30.
Monday Night
Partly cloudy, with a low around 19.
Tuesday
Partly sunny, with a high near 40.
Tuesday Night
A 40 percent chance of snow. Mostly cloudy, with a low around 30.
Wednesday
A 30 percent chance of rain. Mostly cloudy, with a high near 44.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Port Jefferson NY
40.93°N 73.06°W (Elev. 161 ft)
40.93°N 73.06°W (Elev. 161 ft)
6:44 am EST Dec 4, 2025
10am EST Dec 4, 2025-6pm EST Dec 10, 2025
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