Weather on April 21
Naperville, IL
55 Years of Data
Avg High
63°F
Avg Low
41°F
Warmest
1985
74°F avg
Coldest
2011
35°F avg
About This Date
April 21st in Naperville, IL typically brings mild spring weather, with average highs around 63°F and lows near 41°F. Over 55 years of records, the warmest April 21st was in 1985 (74°F average), while the coldest was 2011 (35°F) — a 39°F range across recorded history. Rain or other precipitation has occurred on about 47% of April 21st dates historically, with the wettest April 21st recording 5.08" of rain. The last decade has been 3.0°F cooler on this date compared to 20-30 years ago.
The last decade has been 3.0°F cooler on this date compared to 20-30 years ago.
Planning for April 21st in Naperville, IL? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.
Cooling Trend
1.1°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 61° | 48° | 54° | 1.57" | — |
| 2024 | 46° | 29° | 37° | — | — |
| 2023 | 78° | 41° | 60° | 0.18" | — |
| 2022 | 51° | — | — | 1.02" | — |
| 2021 | 42° | 32° | 37° | 0.41" | — |
| 2020 | — | 35° | — | 0.05" | — |
| 2019 | 65° | 36° | 50° | — | — |
| 2018 | 62° | 29° | 45° | — | — |
| 2017 | 72° | 43° | 57° | — | — |
| 2016 | 71° | 54° | 62° | 1.32" | — |
| 2015 | 50° | 39° | 45° | 0.03" | — |
| 2014 | 80° | 49° | 64° | — | — |
| 2013 | 45° | 30° | 37° | — | — |
| 2012 | 46° | 31° | 38° | 0.05" | — |
| 2011coldest | 44° | 26° | 35° | — | — |
| 2010 | 66° | 36° | 51° | — | — |
| 2009 | 54° | 37° | 45° | 0.3" | — |
| 2008 | 75° | 42° | 59° | — | — |
| 2007 | 69° | 35° | 52° | — | — |
| 2006 | 76° | 41° | 58° | — | — |
| 2005 | 59° | 42° | 51° | — | — |
| 2004 | 63° | 52° | 57° | 1.24" | — |
| 2003 | 59° | 46° | 53° | — | — |
| 2002 | 43° | 36° | 39° | 0.76" | — |
| 2001 | 80° | 54° | 67° | 2.11" | — |
| 2000 | 66° | 38° | 52° | 5.08" | — |
| 1999 | 66° | 45° | 55° | 0.36" | — |
| 1998 | 60° | 46° | 53° | 1.88" | — |
| 1997 | 63° | 43° | 53° | — | — |
| 1996 | 65° | 40° | 52° | 0.08" | — |
| 1995 | 51° | 45° | 48° | 0.2" | — |
| 1994 | 62° | 40° | 51° | — | — |
| 1993 | 56° | 29° | 42° | 0.48" | — |
| 1992 | 68° | 44° | 56° | — | — |
| 1991 | 58° | 37° | 47° | — | — |
| 1990 | 70° | 48° | 59° | 1.19" | — |
| 1989 | 67° | 47° | 57° | — | — |
| 1988 | 52° | 27° | 39° | — | — |
| 1987 | 87° | 50° | 69° | — | — |
| 1986 | 58° | 36° | 47° | — | — |
| 1985warmest | 86° | 63° | 74° | — | — |
| 1984 | 58° | 40° | 49° | — | — |
| 1983 | 65° | 34° | 49° | — | — |
| 1982 | 56° | 29° | 42° | — | — |
| 1981 | 56° | 28° | 42° | — | — |
| 1980 | 81° | 40° | 60° | — | — |
| 1979 | 68° | 49° | 58° | 0.1" | — |
| 1978 | 54° | 33° | 43° | 0.61" | — |
| 1977 | 77° | — | — | — | — |
| 1976 | 66° | 53° | 60° | 0.86" | — |
| 1975 | 50° | 26° | 38° | — | — |
| 1974 | 77° | 59° | 68° | 0.08" | — |
| 1973 | 68° | 57° | 63° | 3.07" | — |
| 1972 | 53° | 39° | 46° | 0.58" | — |
| 1971 | 75° | 39° | 57° | 0.18" | — |
55 years of data from LISLE - MORTON ARBORETUM