Weather on June 18
Naperville, IL
55 Years of Data
Avg High
85°F
Avg Low
60°F
Warmest
2024
85°F avg
Coldest
1999
59°F avg
About This Date
June 18th in Naperville, IL typically brings warm summer weather, with average highs around 85°F and lows near 60°F — a 25°F daily swing. Over 55 years of records, the warmest June 18th was in 2024 (85°F average), while the coldest was 1999 (59°F) — a 26°F range across recorded history. Rain or other precipitation has occurred on about 29% of June 18th dates historically, with the wettest June 18th recording 3.66" of rain. The last decade has been 4.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 4.0°F warmer on this date compared to 20-30 years ago.
Planning for June 18th in Naperville, IL? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
0.7°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 90° | 68° | 79° | 0.81" | — |
| 2024warmest | 95° | 76° | 85° | — | — |
| 2023 | 83° | 53° | 68° | — | — |
| 2022 | 85° | 56° | 70° | — | — |
| 2021 | 89° | 65° | 77° | 0.38" | — |
| 2020 | 87° | 55° | 71° | — | — |
| 2019 | 72° | 53° | 62° | — | — |
| 2018 | 94° | 72° | 83° | — | — |
| 2017 | 85° | 70° | 77° | 0.2" | — |
| 2016 | 85° | 55° | 70° | — | — |
| 2015 | 71° | 56° | 63° | 0.89" | — |
| 2014 | 91° | 75° | 83° | — | — |
| 2013 | 88° | 56° | 72° | 0.25" | — |
| 2012 | 86° | 62° | 74° | — | — |
| 2011 | 87° | 60° | 74° | — | — |
| 2010 | 85° | 59° | 72° | 0.58" | — |
| 2009 | 76° | 60° | 68° | 0.43" | — |
| 2008 | 75° | 52° | 63° | — | — |
| 2007 | 92° | 70° | 81° | — | — |
| 2006 | 91° | 71° | 81° | 0.18" | — |
| 2005 | 72° | 46° | 59° | — | — |
| 2004 | 83° | 64° | 73° | — | — |
| 2003 | 89° | 53° | 71° | — | — |
| 2002 | 87° | 54° | 70° | — | — |
| 2001 | 94° | 64° | 79° | 0.3" | — |
| 2000 | 79° | 54° | 66° | — | — |
| 1999coldest | 76° | 43° | 59° | — | — |
| 1998 | 88° | 66° | 77° | — | — |
| 1997 | 87° | 54° | 70° | — | — |
| 1996 | 87° | 69° | 78° | 3.66" | — |
| 1995 | 91° | 60° | 76° | — | — |
| 1994 | 97° | 68° | 82° | — | — |
| 1993 | 93° | 68° | 81° | 0.48" | — |
| 1992 | 81° | 64° | 72° | 2.72" | — |
| 1991 | 90° | 55° | 72° | — | — |
| 1990 | 84° | 68° | 76° | — | — |
| 1989 | 83° | 47° | 65° | — | — |
| 1988 | 93° | 55° | 74° | — | — |
| 1987 | 95° | 63° | 79° | — | — |
| 1986 | 82° | 50° | 66° | — | — |
| 1985 | 78° | 54° | 66° | — | — |
| 1984 | 90° | 70° | 80° | — | — |
| 1983 | 79° | 60° | 69° | — | — |
| 1982 | 68° | 54° | 61° | — | — |
| 1981 | 83° | — | — | — | — |
| 1980 | 82° | 47° | 64° | — | — |
| 1979 | 75° | 54° | 64° | 1.14" | — |
| 1978 | 89° | 66° | 78° | 0.13" | — |
| 1977 | 89° | 65° | 77° | 0.81" | — |
| 1976 | 86° | 65° | 75° | — | — |
| 1975 | 86° | 62° | 74° | — | — |
| 1974 | 82° | 50° | 66° | 0.03" | — |
| 1973 | 84° | 55° | 70° | — | — |
| 1972 | 78° | 45° | 61° | — | — |
| 1971 | 92° | 57° | 74° | — | — |
55 years of data from LISLE - MORTON ARBORETUM