Philadelphia - Hottest Decades
Ranked here are the hottest decades on record for Philadelphia, Pennsylvania. The lists include decades when Philadelphia had the highest average temperatures, the most hot days and the fewest cold days. These extremes are for temperatures observed at Philadelphia International Airport and cover seven decades, from the 1950s to the 2010s.
That is when Philadelphia 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 | 65.8 | 2010s | 18.8 |
| Runner-up | 65.2 | 1990s | 18.4 |
Warmest Low Temperatures
| Low °F | Decade | Low °C | |
|---|---|---|---|
| Highest | 48.9 | 2010s | 9.4 |
| Runner-up | 47.6 | 2000s, 1990s | 8.7 |
Most Warm Days
| Days | Decade | |
|---|---|---|
| Highest | 172 | 2010s |
| Runner-up | 164 | 2000s |
Most Hot Days
| Days | Decade | |
|---|---|---|
| Highest | 34 | 2010s |
| Runner-up | 31 | 1990s |
Fewest Freezing Days
| Days | Decade | |
|---|---|---|
| Lowest | 76 | 2010s |
| Runner-up | 77 | 1990s |
How Much Hotter are 2010s?
Compared with averages for the previous 50 years (1960 to 2009), the 2010s in Philadelphia had:
- 10 more days each year with temperatures of 90 °F and higher
- 1.9 °F higher daily maximum temperatures (1.0 °C)
- 2.9 °F higher daily minimum temperatures (1.6 °C)
- 15 fewer days a year with freezing temperatures
References
Current Results. 2020. Philadelphia PA 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.