San Rafael Weather in May
Average highs run from 18°C on May 1 to 14°C on May 31, and lows from 5°C to 2°C. Normal precipitation for the month is 28 mm over about 3 wet days.
May day by day
The normal high and low for each date, in °C.
- Normal low
- Normal high
- Reanalysis extreme high
- Reanalysis extreme low
May at a glance
- Average high
- 16°C
- Average low
- 4°C
- Precipitation
- 28 mm
- Reanalysis high
- 30°CMay 22, 2009
- Reanalysis low
- -7°CMay 22, 2019
- Daylight
- 10 h 42 min to 10 h 00 min
- Cloud cover
- 50%
- Humidity
- 60%
- Dew point
- 0°C
- Wind
- 11.9 km/h
Every day of the month
A wet day has at least 1 mm of precipitation in the reanalysis.
| Date | Normal high | Normal low | Reanalysis high | Reanalysis low | Chance wet |
|---|---|---|---|---|---|
| May 1 | 18°C | 5°C | 27°C 1997 | -2°C 2001 | 14% |
| May 2 | 18°C | 5°C | 27°C 2009 | -1°C 2011 | 12% |
| May 3 | 18°C | 5°C | 29°C 2009 | 0°C 2001 | 12% |
| May 4 | 18°C | 5°C | 24°C 2011 | -2°C 1991 | 12% |
| May 5 | 18°C | 5°C | 27°C 1997 | -1°C 2000 | 12% |
| May 6 | 18°C | 5°C | 26°C 1997 | -1°C 2007 | 13% |
| May 7 | 18°C | 5°C | 25°C 2002 | -2°C 2007 | 12% |
| May 8 | 18°C | 5°C | 25°C 1995 | -2°C 2007 | 13% |
| May 9 | 18°C | 5°C | 26°C 2020 | -2°C 2007 | 13% |
| May 10 | 17°C | 5°C | 23°C 1991 | 0°C 1994 | 14% |
| May 11 | 17°C | 5°C | 24°C 1997 | 0°C 1993 | 15% |
| May 12 | 17°C | 5°C | 22°C 1996 | 1°C 2012 | 14% |
| May 13 | 17°C | 4°C | 24°C 2018 | -2°C 1993 | 14% |
| May 14 | 17°C | 4°C | 23°C 2008 | -1°C 2013 | 15% |
| May 15 | 16°C | 4°C | 24°C 1994 | -4°C 2013 | 16% |
| May 16 | 16°C | 4°C | 26°C 2020 | -3°C 2010 | 16% |
| May 17 | 16°C | 4°C | 27°C 1991 | -1°C 2014 | 16% |
| May 18 | 16°C | 4°C | 25°C 2020 | -2°C 2005 | 15% |
| May 19 | 16°C | 3°C | 26°C 2008 | -3°C 2006 | 15% |
| May 20 | 15°C | 3°C | 27°C 2009 | -2°C 1996 | 16% |
| May 21 | 15°C | 3°C | 24°C 2009 | -6°C 2019 | 15% |
| May 22 | 15°C | 3°C | 30°C 2009 | -7°C 2019 | 14% |
| May 23 | 15°C | 3°C | 22°C 2002 | -3°C 1997 | 14% |
| May 24 | 15°C | 3°C | 25°C 2020 | -4°C 1993 | 14% |
| May 25 | 15°C | 3°C | 24°C 2006 | -4°C 1993 | 13% |
| May 26 | 15°C | 2°C | 23°C 2020 | -6°C 1993 | 11% |
| May 27 | 14°C | 2°C | 23°C 2001 | -5°C 2007 | 11% |
| May 28 | 14°C | 2°C | 26°C 1991 | -7°C 2007 | 11% |
| May 29 | 14°C | 2°C | 26°C 1991 | -7°C 2007 | 10% |
| May 30 | 14°C | 2°C | 22°C 2003 | -4°C 1996 | 9% |
| May 31 | 14°C | 2°C | 23°C 1995 | -5°C 1996 | 8% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (GMT-3).
- May 1
- sunrise 8:09 AM, sunset 6:51 PM
- May 31
- sunrise 8:31 AM, sunset 6:31 PM
Other months
Sources
Cloud, humidity, wind and sunshine, and temperature and precipitation: 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 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.