Weather on October 21
Naperville, IL
55 Years of Data
Avg High
63°F
Avg Low
40°F
Warmest
1979
75°F avg
Coldest
1976
37°F avg
About This Date
October 21st in Naperville, IL typically brings mild fall weather, with average highs around 63°F and lows near 40°F. Over 55 years of records, the warmest October 21st was in 1979 (75°F average), while the coldest was 1976 (37°F) — a 38°F range across recorded history. Rain or other precipitation has occurred on about 25% of October 21st dates historically, with the wettest October 21st recording 1.4" 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 October 21st in Naperville, IL? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 67° | 37° | 52° | 0.03" | — |
| 2024 | 78° | 45° | 61° | — | — |
| 2023 | 60° | 36° | 48° | — | — |
| 2022 | 61° | 28° | 44° | — | — |
| 2021 | 73° | 51° | 62° | — | — |
| 2020 | 51° | 38° | 44° | 1.12" | — |
| 2019 | 66° | 43° | 54° | — | — |
| 2018 | 52° | 23° | 37° | — | — |
| 2017 | 79° | 54° | 66° | — | — |
| 2016 | 55° | 41° | 48° | — | — |
| 2015 | 78° | 55° | 67° | 0.38" | — |
| 2014 | 65° | 45° | 55° | — | — |
| 2013 | 62° | 33° | 48° | 0.25" | — |
| 2012 | 59° | 32° | 46° | — | — |
| 2011 | 46° | 34° | 40° | 0.05" | — |
| 2010 | 71° | 38° | 54° | — | — |
| 2009 | 66° | 51° | 59° | — | — |
| 2008 | 56° | 32° | 44° | 0.66" | — |
| 2007 | 74° | 46° | 60° | — | — |
| 2006 | 59° | 48° | 54° | — | — |
| 2005 | 60° | 38° | 49° | — | — |
| 2004 | 60° | 44° | 52° | — | — |
| 2003 | 65° | 48° | 56° | — | — |
| 2002 | 58° | 25° | 41° | — | — |
| 2001 | 73° | 51° | 62° | — | — |
| 2000 | 77° | 46° | 62° | — | — |
| 1999 | 70° | 30° | 50° | — | — |
| 1998 | 61° | 43° | 52° | — | — |
| 1997 | 57° | 34° | 45° | — | — |
| 1996 | 65° | 39° | 52° | — | — |
| 1995 | 46° | 37° | 42° | 0.18" | — |
| 1994 | 73° | 37° | 55° | — | — |
| 1993 | 60° | 38° | 49° | 0.79" | — |
| 1992 | 61° | 39° | 50° | — | — |
| 1991 | 67° | 38° | 52° | — | — |
| 1990 | 63° | 39° | 51° | — | — |
| 1989 | 58° | 36° | 47° | 0.2" | — |
| 1988 | 55° | 30° | 43° | 0.53" | — |
| 1987 | 44° | 31° | 37° | 0.51" | — |
| 1986 | 78° | 49° | 63° | — | — |
| 1985 | 62° | 51° | 57° | — | — |
| 1984 | — | 37° | — | 1.12" | — |
| 1983 | 56° | 47° | 51° | 0.99" | — |
| 1982 | 50° | 29° | 39° | — | — |
| 1981 | 69° | 42° | 56° | — | — |
| 1980 | 58° | 42° | 50° | — | — |
| 1979warmest | 82° | 68° | 75° | — | — |
| 1978 | 78° | 46° | 62° | — | — |
| 1977 | 75° | 44° | 60° | — | — |
| 1976coldest | 44° | 31° | 37° | — | — |
| 1975 | 74° | 39° | 56° | — | — |
| 1974 | 55° | 22° | 38° | — | — |
| 1973 | 68° | 33° | 51° | — | — |
| 1972 | 48° | 40° | 44° | 1.4" | — |
| 1971 | 80° | 56° | 68° | — | — |
55 years of data from LISLE - MORTON ARBORETUM