Historical weather data, all-time temperature records, and monthly climate averages for West Islip, NY. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4th in West Islip lands right in that awkward shoulder season — expect a high around 53° and a low near 38°, with nearly a coin-flip chance of rain. The date has seen a 49-degree swing in recorded history, from a 75° stunner in 2010 down to a 26° freeze in 1972.
West Islip has seen the full extremes of the Northeast — a scorching 104° in July 1966 and a brutal -14° in February 1967, a 118-degree range in just over six decades. The wettest single day on record dropped a staggering 13.51 inches in August 2014, and a January 2022 storm buried the area under 23.5 inches of snow.
Summer is the clear sweet spot, with highs peaking around 82-84° in mid-July — ideal beach weather for this South Shore town. Winters are cold but not brutal, with January and February highs hovering in the upper 30s to 40°. August is the wettest stretch of the year, so pack accordingly if you're visiting late summer.