Weather on September 18
Philadelphia, PA
55 Years of Data
Avg High
78°F
Avg Low
62°F
Warmest
1991
79°F avg
Coldest
1990
57°F avg
About This Date
September 18th in Philadelphia, PA typically brings pleasant fall weather, with average highs around 78°F and lows near 62°F. Over 55 years of records, the warmest September 18th was in 1991 (79°F average), while the coldest was 1990 (57°F) — a 22°F range across recorded history. Rain or other precipitation has occurred on about 24% of September 18th dates historically, with the wettest September 18th recording 4.14" of rain. The last decade has been 2.3°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.3°F warmer on this date compared to 20-30 years ago.
Planning for September 18th in Philadelphia, PA? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 70° | 65° | 67° | — | — |
| 2024 | 77° | 68° | 73° | 0.1" | — |
| 2023 | 81° | 59° | 70° | — | — |
| 2022 | 84° | 66° | 75° | — | — |
| 2021 | 77° | 71° | 74° | — | — |
| 2020 | 74° | 62° | 68° | — | — |
| 2019 | 81° | 67° | 74° | — | — |
| 2018 | 81° | 73° | 77° | 0.18" | — |
| 2017 | 80° | 69° | 75° | — | — |
| 2016 | 84° | 61° | 72° | — | — |
| 2015 | 89° | 66° | 78° | — | — |
| 2014 | 76° | 58° | 67° | — | — |
| 2013 | 66° | 50° | 58° | — | — |
| 2012 | 79° | 58° | 68° | 0.46" | — |
| 2011 | 69° | 55° | 62° | — | — |
| 2010 | 78° | 55° | 67° | — | — |
| 2009 | 76° | 56° | 66° | — | — |
| 2008 | 79° | 57° | 68° | — | — |
| 2007 | 71° | 53° | 62° | — | — |
| 2006 | 85° | 68° | 76° | — | — |
| 2005 | 86° | 67° | 76° | — | — |
| 2004 | 72° | 62° | 67° | — | — |
| 2003 | 74° | 66° | 70° | 2.08" | — |
| 2002 | 82° | 64° | 73° | — | — |
| 2001 | 81° | 60° | 70° | — | — |
| 2000 | 76° | 58° | 67° | 0.08" | — |
| 1999 | 76° | 56° | 66° | — | — |
| 1998 | 81° | 64° | 72° | — | — |
| 1997 | 84° | 70° | 77° | — | — |
| 1996 | 71° | 57° | 64° | 0.48" | — |
| 1995 | 79° | 62° | 70° | 1.07" | — |
| 1994 | 86° | 65° | 75° | 1.45" | — |
| 1993 | 64° | 53° | 59° | 4.14" | — |
| 1992 | 84° | 68° | 76° | — | — |
| 1991warmest | 85° | 73° | 79° | — | — |
| 1990coldest | 67° | 47° | 57° | — | — |
| 1989 | 74° | 64° | 69° | — | — |
| 1988 | 74° | 63° | 68° | — | — |
| 1987 | 77° | 59° | 68° | — | — |
| 1986 | 72° | 54° | 63° | — | — |
| 1985 | 80° | 61° | 70° | — | — |
| 1984 | 76° | 53° | 64° | — | — |
| 1983 | 84° | 64° | 74° | — | — |
| 1982 | 81° | 58° | 69° | — | — |
| 1981 | 67° | 61° | 64° | — | — |
| 1980 | 76° | 62° | 69° | — | — |
| 1979 | 76° | 59° | 67° | — | — |
| 1978 | 86° | 67° | 76° | 0.15" | — |
| 1977 | 85° | 69° | 77° | — | — |
| 1976 | 79° | 65° | 72° | — | — |
| 1975 | 70° | 61° | 65° | 0.23" | — |
| 1974 | 78° | 64° | 71° | — | — |
| 1973 | 76° | 62° | 69° | 0.94" | — |
| 1972 | 81° | 71° | 76° | 0.36" | — |
| 1971 | 78° | 71° | 75° | — | — |
55 years of data from PHILADELPHIA CITY