Cloudy skies · Massachusetts
How cloudy is Boston?
In a typical year, the sky over Boston is mostly cloudy or overcast about 51% of the time, and clear or nearly clear about 36%.
May is the cloudiest month, mostly cloudy about 56% of the time, and August the least cloudy, at about 44%. Across winter, December to February, it’s mostly cloudy about 53% of the time. That makes it the 25th cloudiest sky of the 116 US cities we track.
Last updated
The forecast for the next 48 hours has the sky mostly cloudy about 13% of the time.
Boston’s cloudiest month is May, at about 56% mostly cloudy, so spring here mostly looks like it’s thinking about it.
Live 48-hour forecast from OpenWeatherMap, refreshed about every half hour. Alerts from the National Weather Service.
The sky at a glance
| Mostly cloudy or overcast, all year | 51% |
|---|---|
| Clear or nearly clear, all year | 36% |
| Mostly cloudy, December to February | 53% |
| Cloudiest month | May, 56% |
| Least cloudy month | August, 44% |
Shares of hours across a typical year. Mostly cloudy means at least five eighths of the sky covered; clear or nearly clear means two eighths or less.
Cities with about the same sky
- Baltimore, Maryland: mostly cloudy about 51% of the time
- Minneapolis, Minnesota: mostly cloudy about 51% of the time
- Dayton, Ohio: mostly cloudy about 50% of the time
More about the weather here
Source: NOAA U.S. Climate Normals, hourly, 1991 to 2020, station USW00014739. Airport sensors see cloud up to about 12,000 feet, so thin high cloud isn’t counted.