Spring
58°F / 41°F
March, April, May: about 11.9 in of rain and 7 in of snow.
Plan a visit
Best time to visit Islip
May, July, September bring mild highs and the least rain.
Best time to visit
May · July · September
Highs between 65°F and 85°F with the least rain of the year. Hottest: July (83°F). Coldest nights: January (25°F). Wettest: December.
Islip by season
Month-by-month planner
| Month | Weather | High / low | Rain | Local guides |
|---|---|---|---|---|
| January | Cold | 39°F / 25°F | 3.7 in | |
| February | Wet | 41°F / 26°F | 3.3 in | Valentine’s Day |
| March | Wet | 48°F / 32°F | 4.5 in | St. Patrick’s Day |
| April | Wet | 58°F / 41°F | 4.1 in | |
| May | Wet | 68°F / 51°F | 3.3 in | |
| June | Wet | 77°F / 61°F | 4.0 in | Fourth of July |
| July | Wet | 83°F / 67°F | 3.3 in | Fourth of July |
| August | Wet | 81°F / 66°F | 4.2 in | |
| September | Wet | 75°F / 59°F | 3.6 in | Halloween |
| October | Wet | 64°F / 47°F | 4.0 in | Halloween |
| November | Wet | 54°F / 38°F | 3.4 in | Halloween, Thanksgiving, Christmas |
| December | Wet | 44°F / 30°F | 4.7 in | Christmas, New Year’s Eve |
“Great” means highs between 65°F and 85°F with fewer than 10 wet days. Averages are NOAA’s 1991–2020 normals for the Islip Li Macarthur Ap station, not a forecast.
Around Islip
See Islip before you go
THINGS TO DO · YOUTUBE SHORT
Heckscher State Park, East Islip, NY, US - Part 1
A local activity video shared by OurTrip Videos.
Watch on YouTube ↗
THINGS TO DO · YOUTUBE SHORT
Living Large: Islip
A local activity video shared by CBS New York.
Watch on YouTube ↗Questions
What is the best month to visit Islip?
May, July, September: highs between 65°F and 85°F with the least rain.
What is the hottest month in Islip?
July, averaging 83°F highs.
What is the coldest month in Islip?
January, with average lows of 25°F.
What is the rainiest month in Islip?
December, averaging 4.7 in of precipitation.
When are the big holidays in Islip?
See the local guides: Halloween (October), Thanksgiving (November), Christmas lights (late November to December), New Year’s Eve.