Weather on May 21
Joliet, IL
55 Years of Data
Avg High
74°F
Avg Low
51°F
Warmest
1977
76°F avg
Coldest
2002
42°F avg
About This Date
May 21st in Joliet, IL typically brings pleasant spring weather, with average highs around 74°F and lows near 51°F. Over 53 years of records, the warmest May 21st was in 1977 (76°F average), while the coldest was 2002 (42°F) — a 34°F range across recorded history. Rain or other precipitation has occurred on about 30% of May 21st dates historically, with the wettest May 21st recording 2.54" 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 May 21st in Joliet, 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 | 57° | 51° | 54° | 0.41" | — |
| 2024 | 84° | 59° | 72° | — | — |
| 2023 | 70° | 48° | 59° | — | — |
| 2022 | 84° | 56° | 70° | 0.48" | — |
| 2021 | 82° | 58° | 70° | — | — |
| 2020 | 65° | 41° | 53° | — | — |
| 2019 | 55° | 44° | 50° | 0.64" | — |
| 2018 | 63° | 46° | 54° | 0.1" | — |
| 2017 | 70° | 44° | 57° | 0.89" | — |
| 2016 | 68° | 54° | 61° | — | — |
| 2015 | 49° | 41° | 45° | 0.08" | — |
| 2014 | — | 67° | — | 0.08" | — |
| 2013 | 88° | 63° | 75° | 2.54" | — |
| 2012 | 90° | 57° | 73° | 0.48" | — |
| 2011 | 78° | 53° | 66° | — | — |
| 2010 | 73° | 47° | 60° | 0.99" | — |
| 2009 | 82° | 60° | 71° | — | — |
| 2008 | 65° | 42° | 53° | — | — |
| 2007 | 67° | 47° | 57° | — | — |
| 2006 | 72° | 42° | 57° | — | — |
| 2005 | 70° | 49° | 59° | — | — |
| 2004 | 83° | 58° | 70° | — | — |
| 2003 | 66° | 46° | 56° | — | — |
| 2002coldest | 52° | 33° | 42° | — | — |
| 2001 | 80° | 57° | 69° | 0.15" | — |
| 2000 | 64° | 41° | 53° | — | — |
| 1999 | 80° | 56° | 68° | — | — |
| 1998 | 91° | 55° | 73° | 0.03" | — |
| 1997 | 63° | 42° | 52° | — | — |
| 1996 | 78° | 54° | 66° | 0.51" | — |
| 1995 | 75° | 42° | 59° | — | — |
| 1994 | 71° | 47° | 59° | — | — |
| 1993 | 63° | 42° | 52° | — | — |
| 1992 | 84° | 51° | 68° | — | — |
| 1991 | 83° | 62° | 72° | — | — |
| 1990 | 58° | 49° | 53° | — | — |
| 1989 | 74° | 49° | 61° | — | — |
| 1988 | 80° | 53° | 67° | — | — |
| 1987 | 84° | 59° | 72° | 0.97" | — |
| 1986 | 65° | 39° | 52° | — | — |
| 1985 | 71° | 48° | 60° | 0.38" | — |
| 1984 | 71° | 56° | 63° | 0.56" | — |
| 1983 | 72° | 54° | 63° | — | — |
| 1981 | 77° | 46° | 62° | — | — |
| 1980 | 77° | 47° | 62° | — | — |
| 1979 | 79° | 44° | 61° | — | — |
| 1978 | 81° | 45° | 63° | — | — |
| 1977warmest | 90° | 62° | 76° | — | — |
| 1976 | 88° | 61° | 74° | — | — |
| 1974 | 86° | 65° | 75° | — | — |
| 1973 | 75° | 45° | 60° | — | — |
| 1972 | 89° | 57° | 73° | — | — |
| 1971 | 72° | 43° | 57° | — | — |
53 years of data from JOLIET