Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
Light Snow
31°F
-1°C
| Humidity | 59% |
| Wind Speed | W 13 mph |
| Barometer | 29.96 in (1014.6 mb) |
| Dewpoint | 18°F (-8°C) |
| Visibility | 10.00 mi |
| Wind Chill | 21°F (-6°C) |
| Last update | 19 Jan 3:56 pm EST |
Extended Forecast for
Port Jefferson NY
M.L.King Day

High: 31 °F
Chance
Flurries and
BreezyTonight

Low: 20 °F
Chance
Flurries and
WindyTuesday

High: 23 °F
Sunny and
BreezyTuesday Night
Low: 18 °F
Mostly Clear
and Breezy
then Mostly
ClearWednesday

High: 38 °F
Increasing
CloudsWednesday Night

Low: 36 °F
Mostly Cloudy
and BreezyThursday

High: 41 °F
Mostly Sunny
Thursday Night

Low: 24 °F
Partly Cloudy
Friday
High: 31 °F
Partly Sunny
then Partly
Sunny and
Breezy
Detailed Forecast
M.L.King Day
A chance of flurries. Partly sunny, with a high near 31. Wind chill values between 15 and 20. Breezy, with a southwest wind around 22 mph.
Tonight
A chance of flurries before 10pm. Mostly clear, with a low around 20. Wind chill values between 5 and 15. Windy, with a west wind 23 to 30 mph.
Tuesday
Sunny, with a high near 23. Wind chill values between 5 and 10. Breezy, with a west wind around 23 mph.
Tuesday Night
Mostly clear, with a low around 18. Wind chill values between 5 and 10. Breezy, with a west wind 17 to 22 mph decreasing to 10 to 15 mph after midnight.
Wednesday
Increasing clouds, with a high near 38. South wind 9 to 17 mph.
Wednesday Night
Mostly cloudy, with a steady temperature around 36. Breezy.
Thursday
Mostly sunny, with a high near 41.
Thursday Night
Partly cloudy, with a low around 24.
Friday
Partly sunny, with a high near 31. Breezy.
Friday Night
Mostly cloudy, with a low around 10. Blustery.
Saturday
Mostly cloudy and cold, with a high near 18.
Saturday Night
A 30 percent chance of snow. Mostly cloudy, with a low around 8.
Sunday
A 30 percent chance of snow. Mostly cloudy and cold, with a high near 19.
Sunday Night
A 30 percent chance of snow. Mostly cloudy, with a low around 9.
Monday
Partly sunny, with a high near 23.
Additional Forecasts and Information
Basemap Options
Click map to change the forecast location
Loading map...
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)
3:36 pm EST Jan 19, 2026
4pm EST Jan 19, 2026-6pm EST Jan 26, 2026


