Key Biscayne Weather in May
Average highs run from 85°F on May 1 to 88°F on May 31, and lows from 74°F to 76°F. Normal precipitation for the month is 5.67 in over about 10 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
- 87°F
- Average low
- 75°F
- Precipitation
- 5.67 in
- Record high
- 98°FMay 28, 2017
- Record low
- 55°FMay 6, 1963
- Chance of a freeze
- 0%
- Days of 90°F or more
- 1.0
- Daylight
- 13 h 08 min to 13 h 37 min
- Cloud cover
- 49%
- Humidity
- 75%
- Dew point
- 71°F
- Wind
- 11.0 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 | 85°F | 74°F | 92°F 1971 | 58°F 1999 | 25% |
| May 2 | 85°F | 74°F | 94°F 2026 | 60°F 1955 | 25% |
| May 3 | 85°F | 74°F | 91°F 2023 | 58°F 1955 | 26% |
| May 4 | 85°F | 74°F | 93°F 1951 | 61°F 1971 | 26% |
| May 5 | 86°F | 74°F | 91°F 1998 | 61°F 1955 | 26% |
| May 6 | 86°F | 74°F | 93°F 2010 | 55°F 1963 | 27% |
| May 7 | 86°F | 74°F | 93°F 2021 | 60°F 1951 | 27% |
| May 8 | 86°F | 74°F | 94°F 2022 | 56°F 1992 | 28% |
| May 9 | 86°F | 74°F | 95°F 2010 | 58°F 1960 | 28% |
| May 10 | 86°F | 74°F | 94°F 2024 | 61°F 1960 | 29% |
| May 11 | 86°F | 74°F | 96°F 2008 | 62°F 1960 | 29% |
| May 12 | 86°F | 75°F | 94°F 2008 | 61°F 1989 | 30% |
| May 13 | 86°F | 75°F | 94°F 2019 | 62°F 1981 | 30% |
| May 14 | 86°F | 75°F | 95°F 2019 | 59°F 1960 | 31% |
| May 15 | 86°F | 75°F | 96°F 1995 | 64°F 1960 | 32% |
| May 16 | 86°F | 75°F | 95°F 1995 | 59°F 1951 | 33% |
| May 17 | 87°F | 75°F | 94°F 2008 | 61°F 1951 | 33% |
| May 18 | 87°F | 75°F | 95°F 1989 | 62°F 1950 | 34% |
| May 19 | 87°F | 75°F | 96°F 2024 | 60°F 1951 | 35% |
| May 20 | 87°F | 75°F | 95°F 2008 | 64°F 1951 | 35% |
| May 21 | 87°F | 75°F | 95°F 2008 | 64°F 1949 | 36% |
| May 22 | 87°F | 75°F | 95°F 1990 | 63°F 1948 | 37% |
| May 23 | 87°F | 76°F | 94°F 1951 | 66°F 1948 | 38% |
| May 24 | 87°F | 76°F | 94°F 1989 | 67°F 1951 | 38% |
| May 25 | 87°F | 76°F | 93°F 1949 | 67°F 1951 | 39% |
| May 26 | 88°F | 76°F | 96°F 2024 | 65°F 1950 | 40% |
| May 27 | 88°F | 76°F | 95°F 2017 | 67°F 1967 | 40% |
| May 28 | 88°F | 76°F | 98°F 2017 | 66°F 1983 | 41% |
| May 29 | 88°F | 76°F | 94°F 1951 | 67°F 1951 | 41% |
| May 30 | 88°F | 76°F | 93°F 1996 | 69°F 1948 | 42% |
| May 31 | 88°F | 76°F | 95°F 2026 | 62°F 1971 | 43% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (EDT).
- May 1
- sunrise 6:44 AM, sunset 7:52 PM
- May 31
- sunrise 6:30 AM, sunset 8:07 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00081306 (Cape Florida), public domain. Records: NOAA GHCN-Daily, station USW00012839, 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.