San Francisco - Hottest Decades





Ranked here are the hottest decades on record for San Francisco, California. The lists include decades when San Francisco had the highest average temperatures and the most frequent hot days. These extremes are for temperatures observed in downtown San Francisco and cover ten decades, from the 1920s to the 2010s.

That is when San Francisco had weather measurements that are consistent and complete enough to compare decades. Each decade comprises a standard 10-year range. For instance, the 1990s includes measurements from Jan 1, 1990 to Dec 31, 1999. Links to the data behind these lists are in the References section on this page.

Hottest High Temperatures

Average daily maximum temperature at San Francisco
High °F Decade High °C
Highest 66.1 1990s 19.0
Runner-up 65.1 1980s 18.4

Warmest Low Temperatures

Average daily minimum temperature at San Francisco
Low °F Decade Low °C
Highest 51.9 2010s 11.1
Runner-up 51.6 1990s 10.9

Most Warm Days

Total days per year on average when San Francisco had temperatures of at least 70 °F (21 °C)
Days Decade
Highest 105 1990s
Runner-up 91 1980s

Most Hot Days

Total days per year on average when San Francisco had temperatures of at least 90 °F (32 °C)
Days Decade
Highest 4 1990s, 1980s
Runner-up 3 2000s, 1970s
References

Current Results. 2020. San Francisco CA Temperature Averages by Decade

Jay Lawrimore, Ron Ray, Scott Applequist, Bryant Korzeniewski, Matthew Menne. 2016. Global Summary of the Year, Version 1.0. NOAA National Centers for Environmental Information.

Back to Top