LaSalle County, IL
: September 2026 so far averaged 70°F in LaSalle County, IL, the warmest 1 to 29 September in the county average since 2015, tied 2nd warmest of 76 (with 2015) (county average from NOAA gridded data, 1951 to 2026).
Last updated . This page normally updates every day; the latest update is late.
- High
- 76°F
- Warmest since 2025
- 21st warmest of 76
- Low
- 47.7°F
- Warmest since 2025
- 36th warmest of 76
No measurable precipitation in the county average of LaSalle County, IL for 6 days to Tuesday 29 September 2026 (county average from NOAA gridded data, 1951 to 2026).
- Normal range, 61 to 81°F
Every year as a table
Every 29 September low of the county average in LaSalle County, IL since 1951: 47.7°F in 2026; the lowest is 33.1°F, in 1984.
| Year | High, °F | Low, °F |
|---|---|---|
| 2026 | 76 | 47.7 |
| 2025 | 87.5 | 55.2 |
| 2024 | 74.9 | 59.9 |
| 2023 | 73 | 54.3 |
| 2022 | 62.9 | 35.9 |
| 2021 | 82.6 | 53.6 |
| 2020 | 64.1 | 43.8 |
| 2019 | 67 | 58 |
| 2018 | 64 | 37.9 |
| 2017 | 73.6 | 45.8 |
| 2016 | 63.3 | 49.7 |
| 2015 | 79.4 | 61.1 |
| 2014 | 82.8 | 54 |
| 2013 | 83.9 | 50.2 |
| 2012 | 71.5 | 41.9 |
| 2011 | 68.9 | 47.9 |
| 2010 | 74.1 | 45.8 |
| 2009 | 63.1 | 46.5 |
| 2008 | 75.9 | 53.5 |
| 2007 | 78.1 | 47.3 |
| 2006 | 59.6 | 40.5 |
| 2005 | 73.8 | 41.5 |
| 2004 | 69.7 | 43.1 |
| 2003 | 56.9 | 36.2 |
| 2002 | 80.4 | 51.9 |
| 2001 | 58.1 | 44.8 |
| 2000 | 70.4 | 44.5 |
| 1999 | 62.9 | 48.1 |
| 1998 | 81.2 | 53.9 |
| 1997 | 72.4 | 50.7 |
| 1996 | 64.3 | 44.9 |
| 1995 | 81 | 50.7 |
| 1994 | 67 | 43.4 |
| 1993 | 61.2 | 38.2 |
| 1992 | 61.5 | 35 |
| 1991 | 68.9 | 42.4 |
| 1990 | 70.4 | 50 |
| 1989 | 74 | 42.2 |
| 1988 | 78.3 | 57.3 |
| 1987 | 79.2 | 54.6 |
| 1986 | 84.3 | 66.4 |
| 1985 | 75.7 | 47.2 |
| 1984 | 56.1 | 33.1 |
| 1983 | 80.5 | 54.6 |
| 1982 | 78.5 | 52.6 |
| 1981 | 65.8 | 42.3 |
| 1980 | 68.1 | 46.7 |
| 1979 | 82.4 | 52.6 |
| 1978 | 69.7 | 42.2 |
| 1977 | 72.6 | 47 |
| 1976 | 65.8 | 44.9 |
| 1975 | 71.2 | 48.7 |
| 1974 | 67.1 | 46.2 |
| 1973 | 75.6 | 62.9 |
| 1972 | 75.7 | 46.5 |
| 1971 | 85.4 | 64.7 |
| 1970 | 68.3 | 38.5 |
| 1969 | 72.9 | 45 |
| 1968 | 69.6 | 48.3 |
| 1967 | 52.6 | 34.5 |
| 1966 | 65.9 | 50.4 |
| 1965 | 75.9 | 52.4 |
| 1964 | 64.6 | 36.1 |
| 1963 | 70.5 | 44.3 |
| 1962 | 66.6 | 36.4 |
| 1961 | 63.2 | 36 |
| 1960 | 67.9 | 47 |
| 1959 | 67.6 | 50.9 |
| 1958 | 68.2 | 41 |
| 1957 | 68.6 | 35.2 |
| 1956 | 79.7 | 54.2 |
| 1955 | 72.6 | 51.9 |
| 1954 | 77.7 | 62 |
| 1953 | 94.5 | 58.9 |
| 1952 | 83.1 | 53 |
| 1951 | 60.7 | 33.5 |
The month
August 2026 averaged 72.2°F in LaSalle County, IL, the warmest August in the county average since 2021, tied 58th warmest of 132 (with 2012, 1987 and 1905) (county average from NOAA's monthly county data, 1895 to 2026).
The month in words
- Tuesday 29 September 2026: a high of 76°F averaged over LaSalle County, IL, the warmest 29 September in the county average since 2025, 21st warmest of 76 (county average from NOAA gridded data, 1951 to 2026).
- Tuesday 29 September 2026: a low of 47.7°F averaged over LaSalle County, IL, the warmest 29 September night in the county average since 2025, 36th warmest of 76 (county average from NOAA gridded data, 1951 to 2026).
- Days of the month without a value
- 0
Nearby
Rockford, IL 59.7 mi, the nearest city with its own station