Boston Weather in May
Average highs run from 60°F on May 1 to 70°F on May 31, and lows from 40°F to 51°F. Normal precipitation for the month is 4.14 in over about 14 wet days.
May day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
May at a glance
- Average high
- 65°F
- Average low
- 46°F
- Precipitation
- 4.14 in
- Snowfall
- 0.1 in
- Record high
- 93°FMay 26, 2020
- Record low
- 26°FMay 10, 1947
- Chance of a freeze
- 61%
- Daylight
- 14 h 06 min to 15 h 06 min
- Cloud cover
- 67%
- Humidity
- 78%
- Dew point
- 47°F
- Wind
- 5.4 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| May 1 | 60°F | 40°F | 87°F 1970 | 28°F 1943 | 50% | 6% |
| May 2 | 60°F | 41°F | 84°F 1954 | 31°F 1963 | 50% | 6% |
| May 3 | 60°F | 41°F | 85°F 1944 | 30°F 1939 | 50% | 5% |
| May 4 | 61°F | 41°F | 85°F 1960 | 31°F 2002 | 49% | 5% |
| May 5 | 61°F | 42°F | 90°F 1950 | 31°F 1974 | 49% | 4% |
| May 6 | 62°F | 42°F | 88°F 1959 | 33°F 1968 | 49% | 4% |
| May 7 | 62°F | 43°F | 83°F 1982 | 29°F 1970 | 49% | 4% |
| May 8 | 62°F | 43°F | 88°F 2015 | 29°F 1956 | 49% | 3% |
| May 9 | 63°F | 43°F | 89°F 2015 | 29°F 1947 | 48% | 3% |
| May 10 | 63°F | 44°F | 86°F 1993 | 26°F 1947 | 48% | 3% |
| May 11 | 63°F | 44°F | 89°F 1979 | 31°F 1949 | 48% | 3% |
| May 12 | 64°F | 45°F | 86°F 1953 | 31°F 2020 | 48% | 2% |
| May 13 | 64°F | 45°F | 85°F 2004 | 30°F 2020 | 48% | 2% |
| May 14 | 64°F | 45°F | 88°F 1974 | 32°F 1943 | 48% | 2% |
| May 15 | 65°F | 46°F | 87°F 1961 | 36°F 1977 | 47% | 2% |
| May 16 | 65°F | 46°F | 89°F 1991 | 33°F 1959 | 47% | 1% |
| May 17 | 65°F | 46°F | 87°F 1949 | 32°F 1956 | 47% | 1% |
| May 18 | 66°F | 47°F | 86°F 2026 | 33°F 1981 | 47% | 1% |
| May 19 | 66°F | 47°F | 86°F 1962 | 34°F 2002 | 46% | 1% |
| May 20 | 66°F | 48°F | 90°F 2021 | 33°F 2002 | 46% | 1% |
| May 21 | 67°F | 48°F | 90°F 1977 | 36°F 1967 | 46% | 1% |
| May 22 | 67°F | 48°F | 88°F 1977 | 36°F 1963 | 46% | 1% |
| May 23 | 67°F | 49°F | 90°F 1991 | 33°F 1967 | 45% | 1% |
| May 24 | 68°F | 49°F | 85°F 1977 | 31°F 1963 | 45% | 1% |
| May 25 | 68°F | 49°F | 86°F 1944 | 33°F 1938 | 45% | 1% |
| May 26 | 68°F | 50°F | 93°F 2020 | 37°F 1961 | 45% | 0% |
| May 27 | 68°F | 50°F | 89°F 1978 | 36°F 1969 | 45% | 0% |
| May 28 | 69°F | 50°F | 90°F 2016 | 37°F 1983 | 45% | 0% |
| May 29 | 69°F | 50°F | 87°F 1944 | 38°F 1966 | 44% | 0% |
| May 30 | 69°F | 51°F | 91°F 2006 | 34°F 1961 | 44% | 0% |
| May 31 | 70°F | 51°F | 88°F 2006 | 39°F 1945 | 44% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (EDT).
- May 1
- sunrise 6:09 AM, sunset 8:15 PM
- May 31
- sunrise 5:40 AM, sunset 8:46 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00301625 (Colden 1W), public domain. Records: NOAA GHCN-Daily, station USW00014733, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.