Weather on September 27
Naperville, IL
55 Years of Data
Avg High
74°F
Avg Low
50°F
Warmest
1998
82°F avg
Coldest
1991
45°F avg
About This Date
September 27th in Naperville, IL typically brings pleasant fall weather, with average highs around 74°F and lows near 50°F. Over 55 years of records, the warmest September 27th was in 1998 (82°F average), while the coldest was 1991 (45°F) — a 37°F range across recorded history. Rain or other precipitation has occurred on about 29% of September 27th dates historically, with the wettest September 27th recording 7.32" of rain. The last decade has been 1.1°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.1°F warmer on this date compared to 20-30 years ago.
Planning for September 27th in Naperville, IL? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 83° | 55° | 69° | — | — |
| 2024 | 76° | 47° | 61° | — | — |
| 2023 | 74° | 58° | 66° | 0.15" | — |
| 2022 | 64° | 40° | 52° | — | — |
| 2021 | 83° | 51° | 67° | — | — |
| 2020 | 77° | 61° | 69° | — | — |
| 2019 | 73° | 53° | 63° | — | — |
| 2018 | 68° | 42° | 55° | — | — |
| 2017 | 91° | 61° | 76° | — | — |
| 2016 | 70° | 51° | 60° | — | — |
| 2015 | 77° | 51° | 64° | — | — |
| 2014 | 80° | 49° | 64° | — | — |
| 2013 | 78° | 45° | 61° | — | — |
| 2012 | 69° | 39° | 54° | — | — |
| 2011 | 59° | 52° | 55° | 2.36" | — |
| 2010 | 60° | 43° | 51° | — | — |
| 2009 | 74° | 52° | 63° | 0.84" | — |
| 2008 | 79° | 49° | 64° | — | — |
| 2007 | 71° | 47° | 59° | — | — |
| 2006 | 73° | 50° | 62° | — | — |
| 2005 | 74° | 45° | 59° | — | — |
| 2004 | 76° | 42° | 59° | — | — |
| 2003 | 62° | 46° | 54° | 1.65" | — |
| 2002 | 74° | 55° | 64° | — | — |
| 2001 | 71° | 41° | 56° | — | — |
| 2000 | 74° | 45° | 59° | — | — |
| 1999 | 87° | 58° | 72° | 0.74" | — |
| 1998warmest | 92° | 73° | 82° | — | — |
| 1997 | 79° | 46° | 62° | — | — |
| 1996 | 67° | 54° | 60° | 5.41" | — |
| 1995 | 82° | 50° | 66° | — | — |
| 1994 | 58° | 50° | 54° | 0.15" | — |
| 1993 | 64° | 46° | 55° | 0.97" | — |
| 1992 | 69° | 49° | 59° | 1.73" | — |
| 1991coldest | 60° | 31° | 45° | — | — |
| 1990 | 85° | 47° | 66° | — | — |
| 1989 | 68° | 34° | 51° | — | — |
| 1988 | 83° | 57° | 70° | — | — |
| 1987 | 86° | 63° | 74° | 0.25" | — |
| 1986 | 87° | 67° | 77° | 7.32" | — |
| 1985 | 67° | 43° | 55° | — | — |
| 1984 | 54° | 44° | 49° | 0.05" | — |
| 1983 | 80° | 48° | 64° | 0.05" | — |
| 1982 | 69° | 46° | 58° | — | — |
| 1981 | 76° | 48° | 62° | 2.08" | — |
| 1980 | 68° | 41° | 55° | — | — |
| 1979 | 80° | 50° | 65° | — | — |
| 1978 | 77° | 50° | 64° | — | — |
| 1977 | 75° | 45° | 60° | — | — |
| 1976 | 67° | 51° | 59° | 1.02" | — |
| 1975 | 70° | 36° | 53° | — | — |
| 1974 | 82° | 53° | 68° | — | — |
| 1973 | 85° | 67° | 76° | — | — |
| 1972 | 66° | 47° | 56° | — | — |
| 1971 | 85° | 62° | 73° | 0.56" | — |
55 years of data from LISLE - MORTON ARBORETUM