Weather on March 21 at Gateway Arch
Gateway Arch National Park
Based on 55 years of data from St. Louis, MO
Planning Your Visit
March 21st in Gateway Arch National Park (via St. Louis, MO) typically brings cool spring weather, with average highs around 59°F and lows near 38°F. Over 55 years of records, the warmest March 21st was in 2012 (73°F average), while the coldest was 2013 (27°F) — a 46°F range across recorded history. Precipitation has occurred on 36% of recorded March 21st dates, with snow falling 4% of the time (heaviest snowfall: 5"). The last decade has been 5.7°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.7°F warmer on this date compared to 20-30 years ago.
Planning for March 21st in Gateway Arch? Bring layers as temperatures can vary throughout the day. Consider bringing rain gear or an umbrella.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2026 | 86°F | 48°F | 0" | -- |
| 2025 | 67°F | 28°F | 0" | 0" |
| 2024 | 56°F | 31°F | 0" | 0" |
| 2023 | 51°F | 39°F | 0.1" | 0" |
| 2022 | 76°F | 50°F | 1.09" | 0" |
| 2021 | 68°F | 33°F | 0" | 0" |
| 2020 | 45°F | 34°F | 0" | 0" |
| 2019 | 55°F | 35°F | 0" | 0" |
| 2018 | 50°F | 34°F | 0" | 0" |
| 2017 | 86°F | 46°F | 0" | 0" |
| 2016 | 46°F | 33°F | 0.03" | 0" |
| 2015 | 58°F | 41°F | 0" | 0" |
| 2014 | 69°F | 49°F | 0" | -- |
| 2013 | 35°F | 20°F | 0" | 0" |
| 2012 | 81°F | 65°F | 0" | -- |
| 2011 | 81°F | 47°F | 0" | -- |
| 2010 | 47°F | 37°F | 0.03" | 0" |
| 2009 | 57°F | 36°F | 0.25" | 0" |
| 2008 | 62°F | 36°F | 0" | 0" |
| 2007 | 61°F | 45°F | 0.2" | 0" |
| 2006 | 44°F | 30°F | 1.5" | 0.7" |
| 2005 | 55°F | 36°F | 0" | 0" |
| 2004 | 74°F | 33°F | 0" | 0" |
| 2003 | 65°F | 42°F | 0.2" | 0" |
| 2002 | 46°F | 28°F | 0" | 0" |
| 2001 | 57°F | 32°F | 0" | 0" |
| 2000 | 46°F | 34°F | 0.1" | 0" |
| 1999 | 54°F | 34°F | 0" | 0" |
| 1998 | 36°F | 32°F | 0.33" | 0" |
| 1997 | 68°F | 41°F | 0" | 0" |
| 1996 | 48°F | 26°F | 0" | 0" |
| 1995 | 70°F | 45°F | 0" | 0" |
| 1994 | 70°F | 36°F | 0" | 0" |
| 1993 | 46°F | 39°F | 0.08" | 0" |
| 1992 | 62°F | 33°F | 0" | 0" |
| 1991 | 82°F | 57°F | 0" | 0" |
| 1990 | 70°F | 46°F | 0" | 0" |
| 1989 | 42°F | 22°F | 0.33" | 0" |
| 1988 | 58°F | 39°F | 0" | 0" |
| 1987 | 70°F | 45°F | 0" | 0" |
| 1986 | 41°F | 25°F | 0" | 0" |
| 1985 | 58°F | 44°F | 0.05" | 0" |
| 1984 | 50°F | 33°F | 0" | 0" |
| 1983 | 42°F | 29°F | 0.46" | 0" |
| 1982 | 72°F | 40°F | 0" | 0" |
| 1980 | 64°F | 28°F | -- | 0" |
| 1979 | 59°F | 43°F | 0.69" | 0" |
| 1978 | 63°F | 38°F | 1.78" | -- |
| 1977 | 48°F | 30°F | 0" | 0" |
| 1976 | 75°F | 43°F | 1.22" | 0" |
| 1975 | 75°F | 46°F | 0" | 0" |
| 1974 | 46°F | 25°F | 1.27" | 5" |
| 1973 | 45°F | 32°F | 0.23" | 0" |
| 1972 | 78°F | 58°F | 0.15" | -- |
| 1971 | 49°F | -- | 0" | -- |