NOAA's National Centers for Environmental Information
County Rankings
Chester County, Pennsylvania
December 2009 Average Temperature Rankings
| Period | Value | 1901-2000 Mean | Anomaly | Rank (1895-2025) | Coolest/Warmest Since | Record |
|---|---|---|---|---|---|---|
| December 2009 1-Month | 33.5°F (0.8°C) | 32.3°F (0.2°C) | 1.2°F | 63rd Coolest | Coolest since: | 1989 |
| 68th Warmest | Warmest since: | 2015 | ||||
| Ties: 1897 | ||||||
| Nov– 2-Month | 41.1°F (5.1°C) | 37.4°F (3.0°C) | 3.7°F | 114th Coolest | Coolest since: | 1917 |
| 17th Warmest | Warmest since: | 2015 | ||||
| Oct– 3-Month | 45.0°F (7.2°C) | 42.9°F (6.1°C) | 2.1°F | 99th Coolest | Coolest since: | 1917 |
| 32nd Warmest | Warmest since: | 2015 | ||||
| Sep– 4-Month | 49.9°F (9.9°C) | 48.4°F (9.1°C) | 1.5°F | 92nd Coolest | Coolest since: | 1917 |
| 39th Warmest | Warmest since: | 2015 | ||||
| Ties: 1912, 1913, 1927 | ||||||
| Aug– 5-Month | 54.9°F (12.7°C) | 53.1°F (11.7°C) | 1.8°F | 102nd Coolest | Coolest since: | 1917 |
| 29th Warmest | Warmest since: | 2015 | ||||
| Ties: 1970 | ||||||
| Jul– 6-Month | 57.7°F (14.3°C) | 56.6°F (13.7°C) | 1.1°F | 93rd Coolest | Coolest since: | 1917 |
| 38th Warmest | Warmest since: | 2015 | ||||
| Jun– 7-Month | 59.3°F (15.2°C) | 58.3°F (14.6°C) | 1.0°F | 89th Coolest | Coolest since: | 1917 |
| 42nd Warmest | Warmest since: | 2015 | ||||
| Ties: 1957, 1983 | ||||||
| May– 8-Month | 59.6°F (15.3°C) | 58.6°F (14.8°C) | 1.0°F | 91st Coolest | Coolest since: | 1917 |
| 40th Warmest | Warmest since: | 2015 | ||||
| Ties: 1918, 1982, 2008 | ||||||
| Apr– 9-Month | 58.9°F (14.9°C) | 57.7°F (14.3°C) | 1.2°F | 99th Coolest | Coolest since: | 1917 |
| 32nd Warmest | Warmest since: | 2015 | ||||
| Mar– 10-Month | 57.1°F (13.9°C) | 55.9°F (13.3°C) | 1.2°F | 99th Coolest | Coolest since: | 1917 |
| 32nd Warmest | Warmest since: | 2011 | ||||
| Ties: 1953, 1977, 1985, 1987 | ||||||
| Feb– 11-Month | 55.0°F (12.8°C) | 53.6°F (12.0°C) | 1.4°F | 101st Coolest | Coolest since: | 1904 |
| 30th Warmest | Warmest since: | 2012, 2024 | ||||
| Ties: 1959 | ||||||
| Jan– 12-Month | 52.7°F (11.5°C) | 51.5°F (10.8°C) | 1.2°F | 98th Coolest | Coolest since: | 1904 |
| 33rd Warmest | Warmest since: | 2012 | ||||
| Ties: 1900 | ||||||
| Jul 2008– 18-Month | 54.3°F (12.4°C) | 53.2°F (11.8°C) | 1.1°F | 98th Coolest | Coolest since: | 1904 |
| 32nd Warmest | Warmest since: | 2012 | ||||
| Ties: 1973, 1985, 1995 | ||||||
| Jan 2008– 24-Month | 53.0°F (11.7°C) | 51.5°F (10.8°C) | 1.5°F | 107th Coolest | Coolest since: | 1905 |
| 23rd Warmest | Warmest since: | 2012, 2024 | ||||
| Ties: 2000 | ||||||
| Jan 2007– 36-Month | 53.3°F (11.8°C) | 51.5°F (10.8°C) | 1.8°F | 111th Coolest | Coolest since: | 1905 |
| 18th Warmest | Warmest since: | 2012 | ||||
| Jan 2006– 48-Month | 53.7°F (12.1°C) | 51.5°F (10.8°C) | 2.2°F | 115th Coolest | Coolest since: | 1907 |
| 13th Warmest | Warmest since: | 2023, 2024 | ||||
| Ties: 2001 | ||||||
| Jan 2005– 60-Month | 53.6°F (12.0°C) | 51.5°F (10.8°C) | 2.1°F | 112th Coolest | Coolest since: | 1907 |
| 15th Warmest | Warmest since: | 2024 | ||||
Citing This Page
- NOAA National Centers for Environmental information, Climate at a Glance: County Rankings, published March 2025, retrieved on March 13, 2025 from https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/county/rankings
