Boston Weather in May
Average highs run from 83°F on May 1 to 88°F on May 31, and lows from 57°F to 66°F. Normal precipitation for the month is 3.82 in over about 6 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
- 86°F
- Average low
- 61°F
- Precipitation
- 3.82 in
- Record high
- 101°FMay 25, 1953
- Record low
- 41°FMay 4, 1971
- Chance of a freeze
- 0%
- Days of 90°F or more
- 8.2
- Daylight
- 13 h 23 min to 14 h 00 min
- Cloud cover
- 49%
- Humidity
- 71%
- Dew point
- 63°F
- Wind
- 6.9 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| May 1 | 83°F | 57°F | 92°F 1990 | 45°F 1996 | 19% |
| May 2 | 83°F | 57°F | 96°F 1990 | 45°F 2026 | 19% |
| May 3 | 83°F | 57°F | 95°F 1951 | 46°F 1940 | 19% |
| May 4 | 83°F | 58°F | 93°F 1951 | 41°F 1971 | 19% |
| May 5 | 84°F | 58°F | 95°F 1952 | 45°F 1954 | 19% |
| May 6 | 84°F | 58°F | 95°F 1927 | 45°F 2013 | 19% |
| May 7 | 84°F | 58°F | 96°F 1927 | 47°F 1954 | 19% |
| May 8 | 84°F | 59°F | 97°F 1927 | 44°F 1992 | 19% |
| May 9 | 84°F | 59°F | 98°F 1955 | 45°F 1928 | 19% |
| May 10 | 85°F | 59°F | 99°F 1936 | 46°F 1984 | 19% |
| May 11 | 85°F | 60°F | 99°F 1936 | 47°F 1990 | 19% |
| May 12 | 85°F | 60°F | 94°F 1933 | 42°F 1969 | 19% |
| May 13 | 85°F | 60°F | 95°F 1933 | 44°F 1960 | 20% |
| May 14 | 86°F | 60°F | 96°F 1936 | 44°F 1960 | 20% |
| May 15 | 86°F | 61°F | 95°F 1933 | 51°F 1960 | 20% |
| May 16 | 86°F | 61°F | 95°F 1944 | 48°F 1967 | 21% |
| May 17 | 86°F | 61°F | 94°F 1933 | 49°F 1973 | 21% |
| May 18 | 86°F | 62°F | 95°F 1940 | 47°F 2011 | 22% |
| May 19 | 86°F | 62°F | 97°F 1938 | 47°F 1976 | 22% |
| May 20 | 87°F | 62°F | 98°F 1962 | 45°F 2002 | 22% |
| May 21 | 87°F | 63°F | 98°F 1938 | 48°F 2002 | 23% |
| May 22 | 87°F | 63°F | 98°F 1938 | 47°F 1993 | 23% |
| May 23 | 87°F | 63°F | 99°F 1941 | 48°F 1993 | 24% |
| May 24 | 87°F | 64°F | 100°F 1941 | 52°F 1954 | 24% |
| May 25 | 87°F | 64°F | 101°F 1953 | 52°F 1967 | 25% |
| May 26 | 88°F | 64°F | 99°F 1953 | 48°F 1979 | 25% |
| May 27 | 88°F | 64°F | 100°F 1953 | 49°F 1988 | 26% |
| May 28 | 88°F | 65°F | 100°F 1953 | 49°F 1961 | 27% |
| May 29 | 88°F | 65°F | 97°F 1927 | 53°F 1968 | 27% |
| May 30 | 88°F | 65°F | 98°F 1927 | 52°F 1971 | 28% |
| May 31 | 88°F | 66°F | 99°F 1927 | 49°F 1984 | 29% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (EDT).
- May 1
- sunrise 6:51 AM, sunset 8:14 PM
- May 31
- sunrise 6:33 AM, sunset 8:33 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00085879 (Monticello 5 Se), public domain. Records: NOAA GHCN-Daily, station USC00096087, 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.