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
| High °F | Decade | High °C | |
|---|---|---|---|
| Highest | 66.1 | 1990s | 19.0 |
| Runner-up | 65.1 | 1980s | 18.4 |
Warmest Low Temperatures
| Low °F | Decade | Low °C | |
|---|---|---|---|
| Highest | 51.9 | 2010s | 11.1 |
| Runner-up | 51.6 | 1990s | 10.9 |
Most Warm Days
| Days | Decade | |
|---|---|---|
| Highest | 105 | 1990s |
| Runner-up | 91 | 1980s |
Most Hot Days
| 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.