Historical weather data, all-time temperature records, and monthly climate averages for Watertown, MA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5 in Watertown runs cool, with an average high of 54° and a low of 35° across 58 years of records. The date has seen wild swings though — from a balmy 77° in 2010 down to a bitter 17° in 1995. There's a 41% chance of rain today, with a small but real 8% chance that some of it falls as snow.
Watertown's weather has some serious extremes on its résumé. The thermometer has swung from a record -11° in February 2023 all the way up to 103° as recently as June 2025. On the wet side, a single day in June 1998 dumped 7.15 inches of rain, and the Blizzard of '78 buried the area under 22 inches of snow in one shot.
Summer is peak season here, with highs averaging 85-87° in mid-July and comfortable 75° days stretching into September. January and February are the coldest months, with highs barely cracking the mid-30s. Rain is fairly steady year-round, but late summer — especially early August — is statistically the wettest stretch.