Verdict: Tough month
Boston Weather in January
January is properly cold in Boston, with highs of only 4°C (39°F). Expect showers on roughly 11 days of the month — rarely trip-ruining, worth planning around. If your dates are flexible, most travelers will have a better time in Boston outside January.
Average high
4°C / 39°F
Average low
-4°C / 25°F
Rain days
~11
Precipitation
109 mm
What to pack for Boston in January
- Full winter kit — insulated coat, gloves, warm hat
- A packable rain shell or compact umbrella earns its space
- Comfortable walking shoes — every guide on this site assumes you'll use them
January against the rest of the year
Warmest in Boston: Jul (29°C / 84°F) · Coolest: Jan (4°C / 39°F) · Wettest: Jul (~13 rain days)
4°
-4°
Jan
5°
-5°
Feb
9°
-1°
Mar
13°
4°
Apr
20°
10°
May
26°
15°
Jun
29°
19°
Jul
28°
18°
Aug
23°
14°
Sep
18°
9°
Oct
12°
3°
Nov
6°
-2°
Dec
Daily highs / lows in °C · bars show rain days per month · ERA5 climate normals (2020–2024)