Weather on September 21
Milwaukee, WI
55 Years of Data
Avg High
69°F
Avg Low
53°F
Warmest
2017
77°F avg
Coldest
1995
45°F avg
About This Date
September 21st in Milwaukee, WI typically brings mild fall weather, with average highs around 69°F and lows near 53°F. Over 55 years of records, the warmest September 21st was in 2017 (77°F average), while the coldest was 1995 (45°F) — a 32°F range across recorded history. Rain or other precipitation has occurred on about 42% of September 21st dates historically, with the wettest September 21st recording 1.8" of rain. The last decade has been 9.7°F warmer on this date compared to 20-30 years ago.
The last decade has been 9.7°F warmer on this date compared to 20-30 years ago.
Planning for September 21st in Milwaukee, WI? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.
Warming Trend
2.3°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 79° | 63° | 71° | 1.8" | — |
| 2024 | 87° | 57° | 72° | — | — |
| 2023 | 78° | 60° | 69° | — | — |
| 2022 | 80° | 60° | 70° | — | — |
| 2021 | 77° | 61° | 69° | 0.58" | — |
| 2020 | 73° | 54° | 63° | — | — |
| 2019 | 81° | 69° | 75° | 0.56" | — |
| 2018 | 82° | 51° | 67° | — | — |
| 2017warmest | 85° | 70° | 77° | — | — |
| 2016 | 74° | 64° | 69° | 1.75" | — |
| 2015 | 70° | 51° | 60° | — | — |
| 2014 | 63° | 48° | 55° | — | — |
| 2013 | 61° | 50° | 55° | — | — |
| 2012 | 58° | 49° | 53° | 0.25" | — |
| 2011 | 69° | 55° | 62° | — | — |
| 2010 | 73° | 60° | 67° | 0.03" | — |
| 2009 | 74° | 59° | 66° | 0.76" | — |
| 2008 | 81° | 58° | 69° | — | — |
| 2007 | 78° | — | — | — | — |
| 2006 | 62° | 39° | 51° | — | — |
| 2005 | 85° | 58° | 71° | — | — |
| 2004 | 80° | 54° | 67° | — | — |
| 2003 | 71° | 45° | 58° | — | — |
| 2002 | 72° | 55° | 63° | 0.28" | — |
| 2001 | 75° | 54° | 64° | 0.84" | — |
| 2000 | 61° | 43° | 52° | 1.02" | — |
| 1999 | 60° | 40° | 50° | — | — |
| 1998 | 70° | 53° | 61° | — | — |
| 1997 | 63° | 46° | 54° | — | — |
| 1996 | 74° | 56° | 65° | 0.28" | — |
| 1995coldest | 49° | 42° | 45° | 0.86" | — |
| 1994 | 82° | 65° | 73° | — | — |
| 1993 | 61° | 55° | 58° | — | — |
| 1992 | 68° | 53° | 61° | 0.03" | — |
| 1991 | 64° | 43° | 53° | — | — |
| 1990 | 72° | 52° | 62° | 0.97" | — |
| 1989 | 75° | 57° | 66° | — | — |
| 1988 | 57° | 53° | 55° | — | — |
| 1987 | 64° | 47° | 55° | 0.76" | — |
| 1986 | 70° | 58° | 64° | 0.18" | — |
| 1985 | 61° | 54° | 57° | 1.12" | — |
| 1984 | 70° | 57° | 63° | — | — |
| 1983 | 53° | 41° | 47° | — | — |
| 1982 | 58° | 44° | 51° | — | — |
| 1981 | 61° | 53° | 57° | 1.37" | — |
| 1980 | 75° | 62° | 69° | 0.3" | — |
| 1979 | 64° | 52° | 58° | — | — |
| 1978 | 66° | 50° | 58° | 0.08" | — |
| 1977 | 58° | 51° | 54° | — | — |
| 1976 | 62° | 47° | 54° | — | — |
| 1975 | 56° | 50° | 53° | 0.03" | — |
| 1974 | 64° | 40° | 52° | — | — |
| 1973 | 72° | 51° | 61° | 0.66" | — |
| 1972 | 69° | 50° | 60° | 1.19" | — |
| 1971 | 73° | 48° | 61° | — | — |
55 years of data from W ALLIS