Weather on September 15 at Gateway Arch
Gateway Arch National Park
Based on 53 years of data from St. Louis, MO
Planning Your Visit
September 15th in Gateway Arch National Park (via St. Louis, MO) typically brings warm fall weather, with average highs around 80°F and lows near 58°F. Over 53 years of records, the warmest September 15th was in 2025 (81°F average), while the coldest was 2011 (53°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 26% of September 15th dates historically, with the wettest September 15th recording 3.86" of rain. The last decade has been 4.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 4.0°F warmer on this date compared to 20-30 years ago.
Planning for September 15th in Gateway Arch? Stay hydrated and seek shade during peak afternoon hours.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 94°F | 68°F | 0" | -- |
| 2024 | 85°F | 64°F | 0.76" | 0" |
| 2023 | 82°F | 44°F | 0" | 0" |
| 2022 | 85°F | 55°F | 0" | 0" |
| 2021 | 82°F | 58°F | 0.05" | 0" |
| 2020 | 80°F | 56°F | 0" | 0" |
| 2019 | 92°F | 62°F | 0" | 0" |
| 2018 | 92°F | 64°F | 0" | 0" |
| 2017 | 85°F | -- | 0" | 0" |
| 2016 | 88°F | 71°F | 0" | 0" |
| 2015 | 81°F | 61°F | 0" | 0" |
| 2014 | 72°F | 57°F | 0" | 0" |
| 2013 | 77°F | 65°F | 0" | 0" |
| 2012 | 69°F | 56°F | 0" | 0" |
| 2011 | 63°F | 44°F | 3.86" | -- |
| 2010 | 84°F | 59°F | 0" | 0" |
| 2009 | 80°F | 62°F | 0.18" | 0" |
| 2008 | 71°F | 58°F | 2.11" | 0" |
| 2007 | 72°F | 46°F | 0" | 0" |
| 2006 | 78°F | 51°F | 0" | 0" |
| 2005 | 76°F | 64°F | 3.4" | 0" |
| 2004 | 83°F | 66°F | 0" | 0" |
| 2003 | 74°F | 55°F | 0" | 0" |
| 2002 | 89°F | 62°F | 1.22" | 0" |
| 2001 | 74°F | 52°F | 0" | 0" |
| 2000 | 81°F | 56°F | 0.03" | 0" |
| 1999 | 80°F | 60°F | 0" | 0" |
| 1998 | 77°F | 69°F | 0.46" | 0" |
| 1997 | 85°F | 67°F | 0" | 0" |
| 1996 | 71°F | 46°F | 0" | 0" |
| 1995 | 83°F | 60°F | 0" | 0" |
| 1994 | 90°F | 68°F | 0" | 0" |
| 1993 | 57°F | 51°F | 0.13" | 0" |
| 1992 | 87°F | 65°F | 0" | 0" |
| 1991 | 94°F | 66°F | 0" | 0" |
| 1990 | 82°F | 51°F | 0" | 0" |
| 1989 | 60°F | 55°F | 0.28" | 0" |
| 1988 | 89°F | 63°F | 0" | 0" |
| 1987 | 78°F | 64°F | 0.08" | 0" |
| 1986 | 84°F | 60°F | 0" | 0" |
| 1985 | 75°F | 44°F | 0" | 0" |
| 1982 | 91°F | 66°F | 0.64" | 0" |
| 1981 | 81°F | 63°F | 0" | 0" |
| 1980 | 86°F | 54°F | 0" | 0" |
| 1979 | 70°F | 41°F | 0" | 0" |
| 1978 | 79°F | 53°F | 0" | 0" |
| 1977 | 69°F | 59°F | 1.57" | 0" |
| 1976 | 90°F | 58°F | 0" | 0" |
| 1975 | 72°F | 41°F | 0" | 0" |
| 1974 | 69°F | 47°F | 0" | 0" |
| 1973 | 78°F | 51°F | 0" | 0" |
| 1972 | 77°F | 65°F | 0" | 0" |
| 1971 | 102°F | -- | 0" | 0" |