Weather on September 20
Saint Louis, MO
55 Years of Data
Avg High
81°F
Avg Low
59°F
Warmest
2017
84°F avg
Coldest
1991
48°F avg
About This Date
September 20th in Saint Louis, MO typically brings warm fall weather, with average highs around 81°F and lows near 59°F. Over 53 years of records, the warmest September 20th was in 2017 (84°F average), while the coldest was 1991 (48°F) — a 36°F range across recorded history. Rain or other precipitation has occurred on about 34% of September 20th dates historically, with the wettest September 20th recording 4.22" of rain. The last decade has been 6.6°F warmer on this date compared to 20-30 years ago.
The last decade has been 6.6°F warmer on this date compared to 20-30 years ago.
Planning for September 20th in Saint Louis, MO? Stay hydrated and seek shade during peak afternoon hours. Consider bringing rain gear or an umbrella.
Warming Trend
1.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 89° | 60° | 75° | 0.03" | — |
| 2024 | 95° | 67° | 81° | — | — |
| 2023 | 77° | 56° | 66° | 0.46" | — |
| 2022 | 99° | 67° | 83° | — | — |
| 2021 | 86° | 70° | 78° | — | — |
| 2020 | 77° | 42° | 60° | — | — |
| 2019 | 89° | 66° | 78° | 0.03" | — |
| 2018 | 95° | 72° | 83° | — | — |
| 2017warmest | 95° | 74° | 84° | — | — |
| 2016 | 87° | 69° | 78° | — | — |
| 2015 | 75° | 57° | 66° | — | — |
| 2014 | 79° | 63° | 71° | — | — |
| 2013 | 92° | 69° | 80° | 1.14" | — |
| 2012 | 76° | 57° | 66° | — | — |
| 2011 | 71° | 52° | 61° | — | — |
| 2010 | 75° | 64° | 70° | 1.78" | — |
| 2009 | 79° | 61° | 70° | 0.66" | — |
| 2008 | 81° | 62° | 71° | — | — |
| 2007 | 90° | 64° | 77° | — | — |
| 2006 | 66° | 41° | 54° | — | — |
| 2005 | 91° | 67° | 79° | 4.22" | — |
| 2004 | 84° | 49° | 66° | — | — |
| 2003 | 68° | 47° | 57° | — | — |
| 2002 | 81° | 65° | 73° | 1.57" | — |
| 2001 | 70° | 53° | 61° | — | — |
| 2000 | 92° | 58° | 75° | — | — |
| 1999 | 71° | 59° | 65° | 0.28" | — |
| 1998 | 87° | 66° | 77° | — | — |
| 1997 | 91° | 67° | 79° | — | — |
| 1996 | 75° | 61° | 68° | 0.05" | — |
| 1995 | 65° | 58° | 61° | — | — |
| 1994 | 83° | 51° | 67° | — | — |
| 1993 | 80° | 61° | 70° | 1.73" | — |
| 1992 | 70° | 52° | 61° | 0.69" | — |
| 1991coldest | 59° | 37° | 48° | — | — |
| 1990 | 77° | 63° | 70° | — | — |
| 1989 | 81° | 54° | 67° | — | — |
| 1988 | 81° | 48° | 64° | — | — |
| 1987 | 75° | 47° | 61° | — | — |
| 1986 | 90° | 66° | 78° | 0.1" | — |
| 1985 | 90° | 51° | 70° | — | — |
| 1982 | 75° | 59° | 67° | — | — |
| 1981 | 71° | 45° | 58° | — | — |
| 1980 | 90° | 58° | 74° | — | — |
| 1979 | 82° | 52° | 67° | — | — |
| 1978 | 96° | 70° | 83° | — | — |
| 1977 | 67° | 50° | 58° | 0.08" | — |
| 1976 | 93° | 65° | 79° | 1.5" | — |
| 1975 | 67° | 48° | 57° | 0.1" | — |
| 1974 | 85° | 65° | 75° | — | — |
| 1973 | 69° | 49° | 59° | 0.15" | — |
| 1972 | 93° | 73° | 83° | — | — |
| 1971 | 69° | — | — | 2.49" | — |
53 years of data from ST LOUIS ST LOUIS UNIV