Weather on September 12 at Gateway Arch
Gateway Arch National Park
Based on 53 years of data from St. Louis, MO
Planning Your Visit
September 12th in Gateway Arch National Park (via St. Louis, MO) typically brings warm fall weather, with average highs around 83°F and lows near 60°F. Over 53 years of records, the warmest September 12th was in 2013 (86°F average), while the coldest was 2014 (58°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 25% of September 12th dates historically, with the wettest September 12th recording 3.81" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for September 12th in Gateway Arch? Stay hydrated and seek shade during peak afternoon hours.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 94°F | 58°F | 0" | 0" |
| 2024 | 83°F | 57°F | 0" | 0" |
| 2023 | 78°F | 52°F | 0.25" | 0" |
| 2022 | 80°F | 51°F | 0" | 0" |
| 2021 | 88°F | 63°F | 0" | 0" |
| 2020 | 80°F | 62°F | 0" | 0" |
| 2019 | 92°F | 70°F | 0" | 0" |
| 2018 | 81°F | 57°F | 0" | 0" |
| 2017 | 78°F | 62°F | 0" | 0" |
| 2016 | 80°F | 58°F | 0" | 0" |
| 2015 | 75°F | 54°F | 0" | 0" |
| 2014 | 62°F | 54°F | 0.05" | 0" |
| 2013 | 98°F | 74°F | 0.13" | 0" |
| 2012 | 84°F | 62°F | 0" | 0" |
| 2011 | 63°F | 58°F | 0" | -- |
| 2010 | 79°F | 54°F | 0.25" | 0" |
| 2009 | 82°F | 62°F | 0" | 0" |
| 2008 | 79°F | 64°F | 1.73" | 0" |
| 2007 | 76°F | 52°F | 0" | 0" |
| 2006 | 81°F | 68°F | 0" | 0" |
| 2005 | 90°F | 60°F | 0" | 0" |
| 2004 | 84°F | 57°F | 0" | 0" |
| 2003 | 87°F | 70°F | 0.05" | 0" |
| 2002 | 78°F | 56°F | 0" | 0" |
| 2001 | 86°F | 54°F | 0" | -- |
| 2000 | 92°F | 66°F | 1.19" | 0" |
| 1999 | 85°F | 63°F | 0" | 0" |
| 1998 | 85°F | 58°F | 0" | 0" |
| 1997 | 76°F | 50°F | 0" | 0" |
| 1996 | 87°F | 58°F | 0" | 0" |
| 1995 | 78°F | 63°F | 0" | 0" |
| 1994 | 87°F | 59°F | 0" | 0" |
| 1993 | 87°F | 66°F | 0" | 0" |
| 1992 | 77°F | 50°F | 0" | 0" |
| 1991 | 95°F | 74°F | 0" | 0" |
| 1990 | 87°F | 66°F | 0" | 0" |
| 1989 | 71°F | 51°F | 0.25" | 0" |
| 1988 | 91°F | 68°F | 0.56" | 0" |
| 1987 | 85°F | 58°F | 0.1" | 0" |
| 1986 | 79°F | 52°F | 0" | 0" |
| 1985 | 78°F | 54°F | 0" | 0" |
| 1982 | 86°F | 69°F | 0" | 0" |
| 1981 | 86°F | 63°F | 0" | 0" |
| 1980 | 84°F | 60°F | 0" | 0" |
| 1979 | 85°F | 62°F | 0" | 0" |
| 1978 | 92°F | 70°F | 0" | 0" |
| 1977 | 78°F | 56°F | 0.58" | 0" |
| 1976 | 84°F | 41°F | 0" | 0" |
| 1975 | 77°F | 53°F | 2.29" | 0" |
| 1974 | 76°F | 69°F | 3.81" | 0" |
| 1973 | 77°F | 50°F | 0" | 0" |
| 1972 | 94°F | 73°F | 0" | 0" |
| 1971 | 85°F | -- | 0" | 0" |