Historical weather data, all-time temperature records, and monthly climate averages for Wellesley, MA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5th in Wellesley sits right in the thick of spring's unpredictability — the average high is a mild 54°, but this date has swung from a bitter 17° in 1995 to a t-shirt-worthy 77° in 2010. There's a 41% chance of rain today, so a jacket is smart, though the 8% snow chance is low enough that you're probably safe leaving the boots behind.
Wellesley's weather has real teeth at both extremes — the mercury has soared to 103° as recently as June 2025 and plunged to -11° in February 2023, a 114-degree spread that captures New England at its most uncompromising. A single storm dropped 22 inches of snow in February 1978, and a summer cloudburst in June 1998 dumped 7.15 inches of rain in one day.
If you're chasing warmth, aim for mid-July through late August, when average highs peak at 87° the week of July 16th and stay in the low 80s through summer's end. January and February are the cold core of the year, with highs hovering in the mid-to-upper 30s. August is technically the wettest stretch of the year, so summer visitors should pack accordingly.