Johnson County, IL
: September 2026 so far averaged 77.4°F in Johnson 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
- 80.9°F
- Warmest since 2025
- 23rd warmest of 76
- Low
- 50.8°F
- Warmest since 2025
- 35th warmest of 76
No measurable precipitation in the county average of Johnson County, IL for 17 days to Tuesday 29 September 2026 (county average from NOAA gridded data, 1951 to 2026).
- Normal range, 68.1 to 85.9°F
Every year as a table
Every 29 September low of the county average in Johnson County, IL since 1951: 50.8°F in 2026; the lowest is 37.4°F, in 1951.
| Year | High, °F | Low, °F |
|---|---|---|
| 2026 | 80.9 | 50.8 |
| 2025 | 84.4 | 56.2 |
| 2024 | 67.2 | 63.5 |
| 2023 | 81.3 | 63.5 |
| 2022 | 67.4 | 41.8 |
| 2021 | 85.3 | 60 |
| 2020 | 68.2 | 47 |
| 2019 | 89 | 66.9 |
| 2018 | 74.3 | 49.7 |
| 2017 | 78.3 | 51 |
| 2016 | 71.1 | 50.7 |
| 2015 | 79.1 | 62.8 |
| 2014 | 83.9 | 56.8 |
| 2013 | 80.9 | 60.6 |
| 2012 | 72.4 | 50.5 |
| 2011 | 76.1 | 51 |
| 2010 | 75.5 | 45.5 |
| 2009 | 72.3 | 47.2 |
| 2008 | 85.5 | 53.2 |
| 2007 | 83.9 | 52.3 |
| 2006 | 65.6 | 43.2 |
| 2005 | 80.2 | 47.2 |
| 2004 | 78.2 | 47.1 |
| 2003 | 64.9 | 40.1 |
| 2002 | 82.3 | 57.2 |
| 2001 | 68.1 | 45.1 |
| 2000 | 75.8 | 45.8 |
| 1999 | 90 | 53.2 |
| 1998 | 89.9 | 62.9 |
| 1997 | 80.9 | 51.9 |
| 1996 | 68.1 | 43.4 |
| 1995 | 79.6 | 48.1 |
| 1994 | 75.2 | 44 |
| 1993 | 71.9 | 42.7 |
| 1992 | 73.1 | 41.3 |
| 1991 | 78.4 | 47.9 |
| 1990 | 84.6 | 57.5 |
| 1989 | 71 | 46 |
| 1988 | 78.2 | 58.9 |
| 1987 | 83.8 | 59.8 |
| 1986 | 90.9 | 68.9 |
| 1985 | 72.2 | 45.5 |
| 1984 | 61.3 | 42.2 |
| 1983 | 83.1 | 50.6 |
| 1982 | 78.1 | 50.7 |
| 1981 | 74.2 | 46.6 |
| 1980 | 70.9 | 51.2 |
| 1979 | 80.9 | 58.9 |
| 1978 | 71.7 | 45.6 |
| 1977 | 72.3 | 51.5 |
| 1976 | 70 | 52 |
| 1975 | 69.4 | 44.2 |
| 1974 | 72.5 | 48 |
| 1973 | 81.7 | 67.5 |
| 1972 | 79.8 | 61.8 |
| 1971 | 87.9 | 66.3 |
| 1970 | 74.7 | 44.3 |
| 1969 | 77.5 | 44.9 |
| 1968 | 80 | 49.1 |
| 1967 | 57 | 38.2 |
| 1966 | 72.5 | 47.5 |
| 1965 | 78.3 | 51.9 |
| 1964 | 64.7 | 50.1 |
| 1963 | 76.6 | 51.4 |
| 1962 | 68.6 | 38.8 |
| 1961 | 76 | 44.7 |
| 1960 | 81.2 | 50.5 |
| 1959 | 80.9 | 62.5 |
| 1958 | 68.3 | 45.3 |
| 1957 | 71.9 | 43.7 |
| 1956 | 84.2 | 45.2 |
| 1955 | 88.5 | 62.2 |
| 1954 | 84.2 | 67.9 |
| 1953 | 96.7 | 53 |
| 1952 | 87.8 | 52.1 |
| 1951 | 66.4 | 37.4 |
The month
August 2026 averaged 77.2°F in Johnson County, IL, the warmest August in the county average since 2016, tied 37th warmest of 132 (with 1993) (county average from NOAA's monthly county data, 1895 to 2026).
The month in words
- Tuesday 29 September 2026: a high of 80.9°F averaged over Johnson County, IL, the warmest 29 September in the county average since 2025, tied 23rd warmest of 76 (with 2013, 1997, 1979 and 1 other year) (county average from NOAA gridded data, 1951 to 2026).
- Tuesday 29 September 2026: a low of 50.8°F averaged over Johnson County, IL, the warmest 29 September night in the county average since 2025, 35th warmest of 76 (county average from NOAA gridded data, 1951 to 2026).
- Days of the month without a value
- 0
Nearby
Paducah, KY 28.6 mi, the nearest city with its own station