Weather on May 18
Joliet, IL
55 Years of Data
Avg High
72°F
Avg Low
50°F
Warmest
2001
79°F avg
Coldest
2002
41°F avg
About This Date
May 18th in Joliet, IL typically brings pleasant spring weather, with average highs around 72°F and lows near 50°F. Over 53 years of records, the warmest May 18th was in 2001 (79°F average), while the coldest was 2002 (41°F) — a 38°F range across recorded history. Rain or other precipitation has occurred on about 36% of May 18th dates historically, with the wettest May 18th recording 7.87" of rain. The last decade has been 3.6°F cooler on this date compared to 20-30 years ago.
The last decade has been 3.6°F cooler on this date compared to 20-30 years ago.
Planning for May 18th in Joliet, IL? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.
Cooling Trend
0.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 71° | 48° | 60° | — | — |
| 2024 | 81° | 57° | 69° | — | — |
| 2023 | 65° | 41° | 53° | — | — |
| 2022 | 73° | 53° | 63° | — | — |
| 2021 | 66° | 59° | 63° | — | — |
| 2020 | 68° | 52° | 60° | 7.87" | — |
| 2019 | 58° | 45° | 51° | 0.13" | — |
| 2018 | 78° | 54° | 66° | — | — |
| 2017 | 83° | 68° | 75° | 0.13" | — |
| 2016 | 59° | 41° | 50° | — | — |
| 2015 | 81° | 64° | 72° | 0.03" | — |
| 2014 | 59° | 39° | 49° | — | — |
| 2013 | 79° | 60° | 69° | 0.69" | — |
| 2012 | 75° | 47° | 61° | — | — |
| 2011 | 61° | 43° | 52° | — | — |
| 2010 | 57° | 50° | 54° | 0.79" | — |
| 2009 | 62° | 38° | 50° | — | — |
| 2008 | 73° | 40° | 56° | 0.25" | — |
| 2007 | 62° | 39° | 51° | — | — |
| 2006 | 72° | 45° | 58° | 0.81" | — |
| 2005 | 74° | 48° | 61° | — | — |
| 2004 | 81° | 62° | 71° | 1.22" | — |
| 2003 | 73° | 52° | 62° | — | — |
| 2002coldest | 46° | 35° | 41° | — | — |
| 2001warmest | 92° | 67° | 79° | 0.15" | — |
| 2000 | 72° | 58° | 65° | 0.08" | — |
| 1999 | 77° | 58° | 67° | 0.69" | — |
| 1998 | 87° | 53° | 70° | — | — |
| 1997 | 64° | 46° | 55° | — | — |
| 1996 | 89° | 61° | 75° | — | — |
| 1995 | 76° | 49° | 62° | 0.05" | — |
| 1994 | 64° | 44° | 54° | — | — |
| 1993 | 68° | 44° | 56° | — | — |
| 1992 | 79° | 48° | 63° | — | — |
| 1991 | 59° | 50° | 55° | — | — |
| 1990 | 63° | 49° | 56° | — | — |
| 1989 | 82° | 61° | 71° | — | — |
| 1988 | 67° | 43° | 55° | — | — |
| 1987 | 90° | 57° | 73° | 1.6" | — |
| 1986 | 70° | 46° | 58° | 0.84" | — |
| 1985 | 64° | 45° | 54° | — | — |
| 1984 | 81° | 45° | 63° | — | — |
| 1983 | 62° | 41° | 52° | 0.03" | — |
| 1981 | 59° | 49° | 54° | — | — |
| 1980 | 63° | 52° | 57° | 1.88" | — |
| 1979 | 80° | 52° | 66° | — | — |
| 1978 | 72° | 50° | 61° | — | — |
| 1977 | 90° | 66° | 78° | 0.05" | — |
| 1976 | 60° | 37° | 49° | 0.13" | — |
| 1974 | 62° | 49° | 55° | — | — |
| 1973 | 73° | 43° | 58° | — | — |
| 1972 | 87° | 54° | 70° | — | — |
| 1971 | 89° | 60° | 75° | — | — |
53 years of data from JOLIET