The year at a glance
Averages from 30 years of climate history, 1991-2020
| Boston | Metric | Chelsea |
|---|---|---|
| 201 days | Sunny daysclear or partly cloudy skies | 202 days |
| 44 in | Precipitationper year | 45 in |
| 124 days | Wet daysrain or snow per year | 125 days |
| 50 in | Snowfallper year | 50 in |
| 15 days | Hot daysabove 90 °F | 14 days |
| 94 days | Freezing nightsat or below 32 °F | 97 days |
| 72% | Humidityaverage relative | 72% |
| 52 °F | Average temperatureyear round | 52 °F |
Monthly temperatures
Average daily high and low for each month, in °F. The gap between the two lines is what an ordinary day feels like across the year.
Daily highs
Daily lows
View monthly temperatures as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Boston high | 37 | 39 | 46 | 57 | 67 | 76 | 82 | 81 | 73 | 62 | 52 | 42 |
| Chelsea high | 37 | 39 | 46 | 57 | 67 | 77 | 82 | 81 | 73 | 62 | 52 | 42 |
| Boston low | 23 | 24 | 31 | 41 | 50 | 60 | 66 | 65 | 58 | 47 | 38 | 29 |
| Chelsea low | 22 | 24 | 31 | 40 | 50 | 59 | 66 | 65 | 58 | 47 | 37 | 29 |
Monthly precipitation
Total rain plus melted snow for each month, in inches. Taller bars mean wetter months.
View monthly precipitation as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Boston | 3.7 | 3.3 | 4.6 | 3.9 | 3.2 | 3.4 | 2.9 | 3.4 | 3.4 | 4.3 | 3.7 | 4.6 |
| Chelsea | 3.6 | 3.3 | 4.5 | 4.1 | 3.3 | 3.5 | 2.9 | 3.3 | 3.4 | 4.3 | 3.8 | 4.6 |
Monthly sunny days
Days each month with clear or partly cloudy skies, so compare the same month between cities.
View monthly sunny days as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Boston | 17 | 16 | 16 | 16 | 15 | 15 | 19 | 19 | 17 | 19 | 17 | 16 |
| Chelsea | 17 | 16 | 16 | 15 | 15 | 15 | 19 | 19 | 17 | 19 | 17 | 16 |
Keep comparing
Nearby cities and popular picks for each side of this matchup. Any two cities can be compared from the home page.
Boston vs another city
- Boston vs Winthrop Town, MA
- Boston vs Everett, MA
- Boston vs Quincy, MA
- Boston vs Somerville, MA
- Boston vs Cambridge, MA
- Boston vs New York, NY
- Boston vs Los Angeles, CA
- Boston vs Chicago, IL
- Boston vs Houston, TX
- Boston vs Phoenix, AZ
- Boston vs Philadelphia, PA
Chelsea vs another city
- Chelsea vs Everett, MA
- Chelsea vs Malden, MA
- Chelsea vs Revere, MA
- Chelsea vs Winthrop Town, MA
- Chelsea vs Somerville, MA
- Chelsea vs New York, NY
- Chelsea vs Los Angeles, CA
- Chelsea vs Chicago, IL
- Chelsea vs Houston, TX
- Chelsea vs Phoenix, AZ
- Chelsea vs Philadelphia, PA
About this data
Every figure on this page is a 30 year average computed from daily climate history for 1991-2020, using each city's own coordinates. Wet days count days with measurable precipitation, calibrated against the wet day counts in NOAA's published climate normals. Sunny days count clear plus partly cloudy days, defined as average cloud cover of 63 percent or less and calibrated against NOAA's published sky cover tables. Snowfall figures are model estimates anchored to NOAA station measurements near each city.
Weather data by Open-Meteo.com (CC BY 4.0). Contains modified Copernicus Climate Change Service information (ERA5, ERA5-Land).