San Francisco Weather in May
Average highs run from 35°C on May 1 to 31°C on May 31, and lows from 25°C to 24°C. Normal precipitation for the month is 164 mm over about 19 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
- 33°C
- Average low
- 25°C
- Precipitation
- 164 mm
- Reanalysis high
- 41°CMay 15, 1998
- Reanalysis low
- 21°CMay 22, 2011
- Daylight
- 12 h 37 min to 12 h 53 min
- Cloud cover
- 69%
- Humidity
- 69%
- Dew point
- 21°C
- Wind
- 9.0 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 | 35°C | 25°C | 38°C 2002 | 24°C 2012 | 39% |
| May 2 | 34°C | 25°C | 38°C 1992 | 23°C 2010 | 41% |
| May 3 | 34°C | 25°C | 38°C 1997 | 24°C 1993 | 43% |
| May 4 | 34°C | 25°C | 39°C 2002 | 23°C 2013 | 44% |
| May 5 | 34°C | 25°C | 39°C 2002 | 24°C 2009 | 46% |
| May 6 | 34°C | 25°C | 38°C 1997 | 24°C 1999 | 48% |
| May 7 | 34°C | 25°C | 39°C 1997 | 24°C 1992 | 50% |
| May 8 | 34°C | 25°C | 39°C 1997 | 23°C 2001 | 51% |
| May 9 | 34°C | 25°C | 38°C 2002 | 23°C 2001 | 52% |
| May 10 | 34°C | 25°C | 39°C 1994 | 23°C 2014 | 53% |
| May 11 | 34°C | 25°C | 39°C 2002 | 23°C 2012 | 54% |
| May 12 | 34°C | 25°C | 39°C 1992 | 23°C 2011 | 56% |
| May 13 | 34°C | 25°C | 40°C 1998 | 24°C 1999 | 58% |
| May 14 | 33°C | 25°C | 40°C 1998 | 24°C 1999 | 60% |
| May 15 | 33°C | 25°C | 41°C 1998 | 23°C 2013 | 62% |
| May 16 | 33°C | 25°C | 40°C 1998 | 23°C 2000 | 64% |
| May 17 | 33°C | 25°C | 39°C 1998 | 23°C 2000 | 65% |
| May 18 | 33°C | 25°C | 39°C 1998 | 23°C 2004 | 67% |
| May 19 | 33°C | 25°C | 39°C 1998 | 23°C 2005 | 70% |
| May 20 | 32°C | 25°C | 38°C 1998 | 22°C 2005 | 70% |
| May 21 | 32°C | 25°C | 37°C 2016 | 23°C 1999 | 71% |
| May 22 | 32°C | 25°C | 37°C 2016 | 21°C 2011 | 72% |
| May 23 | 32°C | 24°C | 37°C 1997 | 23°C 2011 | 74% |
| May 24 | 31°C | 24°C | 37°C 2016 | 23°C 2004 | 76% |
| May 25 | 31°C | 24°C | 36°C 2016 | 23°C 2004 | 76% |
| May 26 | 31°C | 24°C | 36°C 2015 | 23°C 1996 | 76% |
| May 27 | 31°C | 24°C | 37°C 2015 | 23°C 2001 | 76% |
| May 28 | 31°C | 24°C | 37°C 1994 | 23°C 2019 | 76% |
| May 29 | 31°C | 24°C | 38°C 1995 | 23°C 2012 | 76% |
| May 30 | 31°C | 24°C | 37°C 1995 | 23°C 2008 | 77% |
| May 31 | 31°C | 24°C | 33°C 1999 | 23°C 2008 | 77% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (CST).
- May 1
- sunrise 5:31 AM, sunset 6:08 PM
- May 31
- sunrise 5:24 AM, sunset 6:17 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 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.