South Boston, Massachusetts, United States climate

Average temperatures, precipitation and all-time records for South Boston, Massachusetts, United States, with every day graded against ~46 years of local climate history (1980–2026). Its warmest month is July, averaging a high of 80°F, and its coldest is January, with an average low of 24°F.

South Boston is a densely populated neighborhood of Boston, Massachusetts, United States, located south and east of the Fort Point Channel and abutting Dorchester Bay. It has undergone several demographic transformations since being annexed to the city of Boston in 1804. via Wikipedia

How today compares

Latest recorded day: 2026-07-24. Each reading placed on South Boston, Massachusetts, United States's own ±7-day seasonal distribution.

High 81°F Normal · 55th pct

Low 58°F Very Low · 2nd pct

Feels-like 85°F Normal · 55th pct

Humidity 11.8 g/m³ Low · 10th pct

Wind 12 mph Above Normal · 71st pct

Gust 17 mph Low · 17th pct

Precip 0.00 in Dry

Open South Boston in the live weather grader →

South Boston average temperatures by month

Typical daily high and low, and average precipitation, for each month in South Boston, Massachusetts, United States, based on 1980–2026 records. The wettest month is January (0.10 in on an average day).

Month	Avg high	Avg low	Avg precip
January	36°F	24°F	0.10 in
February	39°F	25°F	0.10 in
March	45°F	32°F	0.10 in
April	55°F	41°F	0.10 in
May	64°F	50°F	0.10 in
June	74°F	59°F	0.10 in
July	80°F	66°F	0.10 in
August	78°F	65°F	0.10 in
September	72°F	59°F	0.10 in
October	62°F	49°F	0.10 in
November	51°F	38°F	0.10 in
December	41°F	29°F	0.10 in

Jan 8°–48°

Feb 13°–50°

Mar 21°–56°

Apr 34°–65°

May 43°–74°

Jun 53°–84°

Jul 61°–88°

Aug 59°–86°

Sep 51°–80°

Oct 40°–70°

Nov 29°–62°

Dec 18°–53°

Each bar spans the 10th-percentile daily low to the 90th-percentile daily high (the range most days fall within), coloured cold → hot on a shared -10°F to 115°F scale, so the whole year's rhythm reads at a glance.

Thinking of visiting South Boston?

Trips live and die by the weather. See how South Boston's comfort stacks up against where you live. South Boston is pre-loaded, just add your city.

Compare South Boston's comfort with your city →

Record extremes

Hottest day on record: 98°F on 2011-07-22
Coldest day on record: -9°F on 2016-02-14

All South Boston weather records →

Percentiles compare each day to South Boston, Massachusetts, United States's own history, so grades are relative to this location: a “Near Record” day here isn't the same temperature as elsewhere. How the grades work →