Santa Rosa Weather in May
Average highs run from 28°C on May 1 to 26°C on May 31, and lows from 16°C to 12°C. Normal precipitation for the month is 22 mm over about 6 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
- 27°C
- Average low
- 14°C
- Precipitation
- 22 mm
- Reanalysis high
- 38°CMay 1, 2013
- Reanalysis low
- 2°CMay 30, 2007
- Daylight
- 11 h 13 min to 10 h 47 min
- Cloud cover
- 64%
- Humidity
- 67%
- Dew point
- 12°C
- Wind
- 9.7 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 | 28°C | 16°C | 38°C 2013 | 7°C 2008 | 22% |
| May 2 | 28°C | 16°C | 38°C 2013 | 7°C 2012 | 21% |
| May 3 | 28°C | 16°C | 35°C 2013 | 7°C 2011 | 20% |
| May 4 | 28°C | 15°C | 34°C 1994 | 6°C 2011 | 20% |
| May 5 | 28°C | 15°C | 35°C 1994 | 9°C 2004 | 20% |
| May 6 | 28°C | 15°C | 35°C 2010 | 9°C 2001 | 20% |
| May 7 | 28°C | 15°C | 34°C 1994 | 8°C 2000 | 20% |
| May 8 | 28°C | 15°C | 34°C 2017 | 8°C 2007 | 19% |
| May 9 | 27°C | 15°C | 32°C 1992 | 8°C 2007 | 17% |
| May 10 | 27°C | 15°C | 35°C 2013 | 5°C 2007 | 17% |
| May 11 | 27°C | 15°C | 35°C 2009 | 9°C 2007 | 18% |
| May 12 | 27°C | 14°C | 33°C 2009 | 7°C 2010 | 18% |
| May 13 | 27°C | 14°C | 33°C 2005 | 9°C 2010 | 18% |
| May 14 | 27°C | 14°C | 34°C 2002 | 9°C 2004 | 17% |
| May 15 | 27°C | 14°C | 33°C 2018 | 6°C 2004 | 17% |
| May 16 | 27°C | 14°C | 32°C 1992 | 7°C 2004 | 17% |
| May 17 | 27°C | 14°C | 33°C 1992 | 8°C 2001 | 16% |
| May 18 | 26°C | 14°C | 31°C 2009 | 6°C 2010 | 15% |
| May 19 | 26°C | 13°C | 33°C 1994 | 7°C 2016 | 15% |
| May 20 | 26°C | 13°C | 34°C 2009 | 8°C 2006 | 14% |
| May 21 | 26°C | 13°C | 35°C 2014 | 8°C 2006 | 14% |
| May 22 | 26°C | 13°C | 34°C 2009 | 6°C 2005 | 13% |
| May 23 | 26°C | 13°C | 34°C 2009 | 7°C 2020 | 13% |
| May 24 | 26°C | 13°C | 35°C 1994 | 6°C 1997 | 13% |
| May 25 | 26°C | 13°C | 33°C 1998 | 5°C 2007 | 12% |
| May 26 | 26°C | 12°C | 32°C 2001 | 6°C 1993 | 12% |
| May 27 | 26°C | 12°C | 33°C 1991 | 5°C 1993 | 10% |
| May 28 | 26°C | 12°C | 38°C 2013 | 5°C 1993 | 10% |
| May 29 | 26°C | 12°C | 33°C 2005 | 5°C 2007 | 10% |
| May 30 | 26°C | 12°C | 32°C 2001 | 2°C 2007 | 10% |
| May 31 | 26°C | 12°C | 33°C 2001 | 2°C 2008 | 10% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (GMT-3).
- May 1
- sunrise 7:38 AM, sunset 6:51 PM
- May 31
- sunrise 7:52 AM, sunset 6:39 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.