Weather on August 18
Naperville, IL
55 Years of Data
Avg High
84°F
Avg Low
61°F
Warmest
1988
87°F avg
Coldest
2008
59°F avg
About This Date
August 18th in Naperville, IL typically brings warm summer weather, with average highs around 84°F and lows near 61°F. Over 54 years of records, the warmest August 18th was in 1988 (87°F average), while the coldest was 2008 (59°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 28% of August 18th dates historically, with the wettest August 18th recording 5.28" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for August 18th in Naperville, IL? Stay hydrated and seek shade during peak afternoon hours.
Cooling Trend
0.5°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 85° | 71° | 78° | — | — |
| 2024 | 82° | 64° | 73° | 0.28" | — |
| 2023 | 79° | 51° | 65° | 1.85" | — |
| 2022 | 83° | 54° | 68° | — | — |
| 2021 | 84° | 63° | 73° | — | — |
| 2020 | 85° | 60° | 72° | — | — |
| 2019 | 76° | 64° | 70° | 2.03" | — |
| 2018 | 85° | 65° | 75° | — | — |
| 2017 | 82° | 65° | 73° | 0.03" | — |
| 2016 | 87° | 67° | 77° | 2.26" | — |
| 2015 | 89° | 67° | 78° | 3.38" | — |
| 2014 | 74° | 64° | 69° | 0.08" | — |
| 2013 | 81° | 51° | 66° | — | — |
| 2012 | 76° | 48° | 62° | — | — |
| 2011 | 84° | 58° | 71° | — | — |
| 2010 | 78° | 63° | 70° | 0.28" | — |
| 2009 | 83° | 56° | 69° | — | — |
| 2008coldest | 75° | 43° | 59° | — | — |
| 2007 | 79° | 55° | 67° | — | — |
| 2006 | 82° | 67° | 74° | — | — |
| 2005 | 85° | 66° | 75° | — | — |
| 2004 | 82° | 63° | 72° | 0.91" | — |
| 2003 | 83° | 62° | 72° | — | — |
| 2002 | 87° | 51° | 69° | — | — |
| 2001 | 81° | 59° | 70° | — | — |
| 2000 | 79° | 63° | 71° | 0.97" | — |
| 1999 | 88° | 60° | 74° | — | — |
| 1998 | 86° | 66° | 76° | — | — |
| 1997 | 77° | 60° | 69° | 0.3" | — |
| 1996 | 82° | 59° | 71° | — | — |
| 1995 | 92° | 78° | 85° | — | — |
| 1994 | 84° | 60° | 72° | — | — |
| 1993 | 87° | 67° | 77° | — | — |
| 1992 | 79° | 55° | 67° | — | — |
| 1991 | 88° | 66° | 77° | — | — |
| 1990 | 90° | 69° | 79° | — | — |
| 1989 | 81° | 55° | 68° | — | — |
| 1988warmest | 98° | 75° | 87° | — | — |
| 1987 | 84° | 61° | 72° | — | — |
| 1985 | 82° | 68° | 75° | — | — |
| 1984 | 85° | 63° | 74° | 0.15" | — |
| 1983 | 92° | 72° | 82° | 0.18" | — |
| 1982 | 84° | 52° | 68° | — | — |
| 1981 | 77° | 48° | 63° | — | — |
| 1980 | 85° | 64° | 74° | 2.21" | — |
| 1979 | 78° | 65° | 71° | 5.28" | — |
| 1978 | 88° | 71° | 79° | — | — |
| 1977 | 77° | 48° | 63° | — | — |
| 1976 | 85° | 53° | 69° | — | — |
| 1975 | 85° | 55° | 70° | — | — |
| 1974 | 85° | 55° | 70° | — | — |
| 1973 | 89° | 62° | 76° | — | — |
| 1972 | 93° | 70° | 81° | — | — |
| 1971 | 88° | 54° | 71° | — | — |
54 years of data from WHEATON 3 SE