Weather on August 31
Naperville, IL
55 Years of Data
Avg High
82°F
Avg Low
59°F
Warmest
1995
83°F avg
Coldest
2009
55°F avg
About This Date
August 31st in Naperville, IL typically brings warm summer weather, with average highs around 82°F and lows near 59°F. Over 54 years of records, the warmest August 31st was in 1995 (83°F average), while the coldest was 2009 (55°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 22% of August 31st dates historically, with the wettest August 31st recording 2.03" of rain. The last decade has been 5.9°F cooler on this date compared to 20-30 years ago.
The last decade has been 5.9°F cooler on this date compared to 20-30 years ago.
Planning for August 31st in Naperville, IL? Stay hydrated and seek shade during peak afternoon hours.
Cooling Trend
1.1°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 73° | 51° | 62° | — | — |
| 2024 | 84° | 62° | 73° | — | — |
| 2023 | 70° | 45° | 57° | — | — |
| 2022 | 80° | 56° | 68° | — | — |
| 2021 | 85° | 58° | 71° | — | — |
| 2020 | 80° | 53° | 67° | — | — |
| 2019 | 73° | 53° | 63° | — | — |
| 2018 | 74° | 53° | 63° | — | — |
| 2017 | 82° | 59° | 71° | — | — |
| 2016 | — | 67° | — | 0.2" | — |
| 2015 | 78° | 58° | 68° | 0.08" | — |
| 2014 | 83° | 68° | 75° | — | — |
| 2013 | 95° | 68° | 82° | 2.03" | — |
| 2012 | 90° | 64° | 77° | — | — |
| 2011 | 77° | 55° | 66° | 0.2" | — |
| 2010 | 87° | 71° | 79° | — | — |
| 2009coldest | 68° | 42° | 55° | — | — |
| 2008 | 82° | 52° | 67° | — | — |
| 2007 | 76° | 51° | 63° | — | — |
| 2006 | 74° | 60° | 67° | — | — |
| 2005 | 80° | 62° | 71° | — | — |
| 2004 | 81° | 61° | 71° | — | — |
| 2003 | 74° | 56° | 65° | — | — |
| 2002 | 85° | 57° | 71° | — | — |
| 2001 | 88° | 64° | 76° | 1.17" | — |
| 2000 | 95° | 71° | 83° | — | — |
| 1999 | 82° | 50° | 66° | — | — |
| 1998 | 85° | 55° | 70° | — | — |
| 1997 | 87° | 66° | 77° | 0.13" | — |
| 1996 | 85° | 56° | 70° | — | — |
| 1995warmest | 92° | 75° | 83° | — | — |
| 1994 | 70° | 58° | 64° | 1.83" | — |
| 1993 | 90° | 62° | 76° | 0.69" | — |
| 1992 | 76° | 50° | 63° | — | — |
| 1991 | 87° | 67° | 77° | — | — |
| 1990 | 83° | 54° | 68° | — | — |
| 1989 | 83° | 57° | 70° | — | — |
| 1988 | 85° | 57° | 71° | — | — |
| 1987 | 74° | 54° | 64° | — | — |
| 1985 | 80° | 52° | 66° | — | — |
| 1984 | 85° | 48° | 66° | — | — |
| 1983 | 84° | 66° | 75° | — | — |
| 1982 | 79° | 62° | 70° | — | — |
| 1981 | 84° | 67° | 75° | 0.51" | — |
| 1980 | 82° | 65° | 73° | 1.5" | — |
| 1979 | 86° | 60° | 73° | — | — |
| 1978 | 84° | 54° | 69° | — | — |
| 1977 | 89° | 67° | 78° | — | — |
| 1976 | 89° | 58° | 73° | — | — |
| 1975 | 72° | 62° | 67° | 0.18" | — |
| 1974 | 80° | 57° | 69° | 0.15" | — |
| 1973 | 91° | 69° | 80° | — | — |
| 1972 | 87° | 65° | 76° | — | — |
| 1971 | 86° | 58° | 72° | — | — |
54 years of data from LISLE - MORTON ARBORETUM