Mason County, IL
: September 2026 so far averaged 73.7°F in Mason 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.
- High
- 78.8°F
- Warmest since 2025
- 25th warmest of 76
- Low
- 47.5°F
- Coldest since 2022
- 33rd coldest of 76
No measurable precipitation in the county average of Mason County, IL for 6 days to Tuesday 29 September 2026 (county average from NOAA gridded data, 1951 to 2026).
- Normal range, 40.8 to 55.8°F
Every year as a table
Every 29 September high of the county average in Mason County, IL since 1951: 78.8°F in 2026; the highest is 97.4°F, in 1953.
| Year | High, °F | Low, °F |
|---|---|---|
| 2026 | 78.8 | 47.5 |
| 2025 | 90.3 | 53.9 |
| 2024 | 76.4 | 61.4 |
| 2023 | 75.7 | 55.5 |
| 2022 | 64.6 | 37.2 |
| 2021 | 88.6 | 57.4 |
| 2020 | 66.5 | 44.7 |
| 2019 | 81.3 | 63.6 |
| 2018 | 69.8 | 46 |
| 2017 | 74.8 | 46.5 |
| 2016 | 62.7 | 51.4 |
| 2015 | 81.2 | 61.1 |
| 2014 | 84.9 | 55 |
| 2013 | 81.9 | 51 |
| 2012 | 71 | 42.4 |
| 2011 | 70.5 | 48.5 |
| 2010 | 75.8 | 47.2 |
| 2009 | 64.7 | 49.2 |
| 2008 | 80.3 | 55.3 |
| 2007 | 82.6 | 49.5 |
| 2006 | 63.2 | 41 |
| 2005 | 73.9 | 43.8 |
| 2004 | 72.5 | 41.3 |
| 2003 | 60.1 | 36.3 |
| 2002 | 82.2 | 53.5 |
| 2001 | 63.2 | 42.2 |
| 2000 | 73.9 | 45.3 |
| 1999 | 64.4 | 48 |
| 1998 | 83.4 | 59.8 |
| 1997 | 75.3 | 51.5 |
| 1996 | 69.7 | 43.6 |
| 1995 | 81.1 | 51.5 |
| 1994 | 72.9 | 44.2 |
| 1993 | 64.5 | 38.5 |
| 1992 | 62.9 | 37.4 |
| 1991 | 75.1 | 47.9 |
| 1990 | 75.4 | 54.6 |
| 1989 | 74.7 | 40.3 |
| 1988 | 83.1 | 58 |
| 1987 | 82.8 | 56.1 |
| 1986 | 89 | 70.1 |
| 1985 | 76.9 | 48.1 |
| 1984 | 57.3 | 34.9 |
| 1983 | 85.1 | 54.6 |
| 1982 | 80.1 | 55.7 |
| 1981 | 69.8 | 45.8 |
| 1980 | 78 | 45.5 |
| 1979 | 85.6 | 55.9 |
| 1978 | 70.2 | 42.4 |
| 1977 | 73.5 | 46.9 |
| 1976 | 65.9 | 47.9 |
| 1975 | 70.6 | 47.7 |
| 1974 | 68.9 | 46.7 |
| 1973 | 79.9 | 65.3 |
| 1972 | 78.5 | 49 |
| 1971 | 88.2 | 66.9 |
| 1970 | 72.6 | 43.8 |
| 1969 | 76.9 | 48.9 |
| 1968 | 74 | 48.8 |
| 1967 | 56 | 35.8 |
| 1966 | 69.3 | 51 |
| 1965 | 78.2 | 51.3 |
| 1964 | 68.5 | 38.5 |
| 1963 | 77.6 | 46.3 |
| 1962 | 70.6 | 36.9 |
| 1961 | 67.4 | 39.4 |
| 1960 | 73.7 | 48.8 |
| 1959 | 72.8 | 52.6 |
| 1958 | 70.5 | 41.7 |
| 1957 | 71.1 | 37.1 |
| 1956 | 83.5 | 53.5 |
| 1955 | 80.3 | 57.5 |
| 1954 | 83.6 | 64.2 |
| 1953 | 97.4 | 62.9 |
| 1952 | 88.3 | 54.9 |
| 1951 | 61.8 | 35.7 |
The month
August 2026 averaged 74.7°F in Mason County, IL, the warmest August in the county average since 2021, tied 48th warmest of 132 (with 1956, 1953 and 1895) (county average from NOAA's monthly county data, 1895 to 2026).
The month in words
- Tuesday 29 September 2026: a high of 78.8°F averaged over Mason County, IL, the warmest 29 September in the county average since 2025, 25th warmest of 76 (county average from NOAA gridded data, 1951 to 2026).
- Tuesday 29 September 2026: a low of 47.5°F averaged over Mason County, IL, the coldest 29 September night in the county average since 2022, 33rd coldest of 76 (county average from NOAA gridded data, 1951 to 2026).
- Days of the month without a value
- 0
Nearby
Springfield, IL 29.7 mi, the nearest city with its own station