Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
A Few Clouds
27°F
-3°C
| Humidity | 43% |
| Wind Speed | W 18 mph |
| Barometer | 29.85 in (1010.8 mb) |
| Dewpoint | 7°F (-14°C) |
| Visibility | 10.00 mi |
| Wind Chill | 14°F (-10°C) |
| Last update | 16 Jan 10:56 am EST |
Extended Forecast for
Port Jefferson NY
Today

High: 35 °F
Sunny and
BreezyTonight
Low: 32 °F
Mostly Cloudy
then Chance
SnowSaturday

High: 37 °F
Rain/Snow
LikelySaturday Night
Low: 33 °F
Mostly Cloudy
then Slight
Chance SnowSunday

High: 36 °F
Chance
Rain/SnowSunday Night

Low: 26 °F
Partly Cloudy
M.L.King Day
High: 33 °F
Sunny then
Mostly Sunny
and BreezyMonday Night

Low: 18 °F
Mostly Clear
and WindyTuesday

High: 23 °F
Sunny and
Breezy
Detailed Forecast
Today
Sunny, with a high near 35. Wind chill values between 15 and 25. Breezy, with a west wind 16 to 22 mph.
Tonight
A 30 percent chance of snow after 1am. Mostly cloudy, with a low around 32. Wind chill values between 25 and 30. South wind 9 to 14 mph.
Saturday
Rain likely, possibly mixed with snow. Mostly cloudy, with a steady temperature around 37. Southwest wind 9 to 11 mph. Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.
Saturday Night
A slight chance of snow before 7pm, then a slight chance of snow after 1am. Mostly cloudy, with a low around 33. West wind 8 to 11 mph. Chance of precipitation is 20%.
Sunday
A slight chance of snow before 10am, then a slight chance of rain between 10am and 1pm, then a chance of snow after 1pm. Cloudy, with a high near 36. West wind 8 to 10 mph. Chance of precipitation is 30%.
Sunday Night
Partly cloudy, with a low around 26.
M.L.King Day
Sunny, with a high near 33. Breezy.
Monday Night
Mostly clear, with a low around 18. Windy.
Tuesday
Sunny, with a high near 23. Breezy.
Tuesday Night
Mostly clear, with a low around 17. Breezy.
Wednesday
Mostly sunny, with a high near 32.
Wednesday Night
Mostly cloudy, with a low around 28.
Thursday
Partly sunny, with a high near 37.
Additional Forecasts and Information
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ABOUT THIS FORECAST
Point Forecast:
Port Jefferson NY
40.96°N 73.08°W (Elev. 3 ft)
40.96°N 73.08°W (Elev. 3 ft)
11:24 am EST Jan 16, 2026
11am EST Jan 16, 2026-6pm EST Jan 22, 2026


