St. Clair County, IL
: September 2026 so far averaged 77.1°F in St. Clair County, IL, the warmest 1 to 29 September in the county average since the data begin in 1951 (county average from NOAA gridded data, 1951 to 2026).
Last updated . This page normally updates every day; the latest update is late.
- Tuesday 29 September 2026: a high of 81.8°F averaged over St. Clair County, IL, the warmest 29 September in the county average since 2025, 24th warmest of 76 (county average from NOAA gridded data, 1951 to 2026).
- Tuesday 29 September 2026: a low of 51°F averaged over St. Clair County, IL, the warmest 29 September night in the county average since 2025, 37th warmest of 76 (county average from NOAA gridded data, 1951 to 2026).
- No measurable precipitation in the county average of St. Clair County, IL for 7 days to Tuesday 29 September 2026 (county average from NOAA gridded data, 1951 to 2026).
The month
- August 2026 averaged 77.5°F in St. Clair County, IL, the warmest August in the county average since 2021, tied 38th warmest of 132 (with 1957 and 1914) (county average from NOAA's monthly county data, 1895 to 2026).
- Days of the month without a value
- 0
Every year on this date
- Above the normal range
- In it
- Below it
- Normal range
- This year and the extreme
Every year as a table
| Year | High, °F | Low, °F |
|---|---|---|
| 2026 | 81.8 | 51 |
| 2025 | 88.2 | 56.1 |
| 2024 | 75 | 64.5 |
| 2023 | 84.1 | 62.3 |
| 2022 | 66.9 | 39.8 |
| 2021 | 87.8 | 60.9 |
| 2020 | 68 | 46.5 |
| 2019 | 85.4 | 67.5 |
| 2018 | 76.9 | 49.9 |
| 2017 | 76.2 | 48.5 |
| 2016 | 67.6 | 52.6 |
| 2015 | 82.9 | 64.6 |
| 2014 | 85.5 | 54.9 |
| 2013 | 84.5 | 58 |
| 2012 | 70.9 | 49.2 |
| 2011 | 75.3 | 54.9 |
| 2010 | 75.7 | 49.2 |
| 2009 | 68.8 | 48 |
| 2008 | 83.5 | 57 |
| 2007 | 84.9 | 53.5 |
| 2006 | 65 | 44.9 |
| 2005 | 80.5 | 46.9 |
| 2004 | 74.3 | 44 |
| 2003 | 62.8 | 39.4 |
| 2002 | 83.2 | 55.6 |
| 2001 | 67.2 | 43.8 |
| 2000 | 74.3 | 46.4 |
| 1999 | 85.5 | 52.9 |
| 1998 | 86.1 | 63.7 |
| 1997 | 73.2 | 52.8 |
| 1996 | 69 | 44.3 |
| 1995 | 80.4 | 49.6 |
| 1994 | 73.8 | 44.6 |
| 1993 | 71.4 | 42.4 |
| 1992 | 69.2 | 38.8 |
| 1991 | 79.3 | 51.3 |
| 1990 | 84.3 | 59.4 |
| 1989 | 75.3 | 43.2 |
| 1988 | 80.3 | 60 |
| 1987 | 80.7 | 59.6 |
| 1986 | 90.1 | 71.1 |
| 1985 | 75.7 | 47.7 |
| 1984 | 60.5 | 41.7 |
| 1983 | 84 | 52.9 |
| 1982 | 77.7 | 54.8 |
| 1981 | 72.9 | 50.4 |
| 1980 | 71.2 | 49.8 |
| 1979 | 85.8 | 56.3 |
| 1978 | 72.7 | 44 |
| 1977 | 74.2 | 53.2 |
| 1976 | 71.5 | 50.1 |
| 1975 | 72.6 | 49.5 |
| 1974 | 68.8 | 46.4 |
| 1973 | 81.2 | 62.6 |
| 1972 | 81.9 | 57.6 |
| 1971 | 91 | 68.2 |
| 1970 | 75 | 47.1 |
| 1969 | 75.8 | 48.8 |
| 1968 | 80.3 | 50.7 |
| 1967 | 60.2 | 39 |
| 1966 | 71.5 | 47.9 |
| 1965 | 78 | 51.7 |
| 1964 | 70.8 | 44.9 |
| 1963 | 78.6 | 51.8 |
| 1962 | 70.7 | 39.5 |
| 1961 | 74.2 | 43.6 |
| 1960 | 80.8 | 48.9 |
| 1959 | 80 | 59.2 |
| 1958 | 68.3 | 44.3 |
| 1957 | 72.9 | 40.9 |
| 1956 | 85.5 | 51.1 |
| 1955 | 89 | 63.2 |
| 1954 | 84.1 | 70.9 |
| 1953 | 98.8 | 61.4 |
| 1952 | 91.1 | 54.1 |
| 1951 | 64.8 | 37.4 |
Nearby
St Louis, MO 30.9 mi, the nearest city with its own station