Historical weather data, all-time temperature records, and monthly climate averages for Stony Brook, NY. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4th in Stony Brook sits squarely in the transition zone — expect a high around 53° and a low near 38°, though the date has swung anywhere from 75° (2010) to a bitter 26° (1972). Nearly half the time, 48%, you'll see some precipitation, though snow is essentially off the table by now.
Stony Brook's weather history has some sharp edges: a scorching 104° on July 3, 1966 and a brutal -14° on February 13, 1967 define the extremes of life on Long Island's North Shore. The wettest single day on record — 13.51" on August 13, 2014 — hints at the region's vulnerability to late-summer deluges, while a 23.5" snowfall on January 29, 2022 is a reminder that winters here can still deliver.
Summer is the main event, with highs peaking around 82–84° in mid-July before a gradual slide through fall. Winters are cold but not brutal, with January and February highs hovering in the upper 30s to 40°. If you're watching your umbrella, late summer is the wettest stretch — the week of August 13–19 averages 1.24" of precipitation, and history shows it can be far worse.