Weather on August 21
Rockford, IL
55 Years of Data
About This Date
August 21st in Rockford, IL typically brings warm summer weather, with average highs around 82°F and lows near 61°F. Over 55 years of records, the warmest August 21st was in 2003 (85°F average), while the coldest was 1985 (61°F) — a 24°F range across recorded history. Rain or other precipitation has occurred on about 31% of August 21st dates historically, with the wettest August 21st recording 7.21" 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 August 21st in Rockford, IL? Stay hydrated and seek shade during peak afternoon hours. Consider bringing rain gear or an umbrella.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 79° | 61° | 70° | — | — |
| 2024 | 76° | 49° | 62° | — | — |
| 2023 | 84° | 66° | 75° | — | — |
| 2022 | 81° | 62° | 71° | — | — |
| 2021 | 87° | 71° | 79° | — | — |
| 2020 | 85° | 58° | 71° | — | — |
| 2019 | 82° | 65° | 73° | 1.14" | — |
| 2018 | 78° | 59° | 69° | 0.28" | — |
| 2017 | 84° | 67° | 75° | — | — |
| 2016 | 76° | 56° | 66° | — | — |
| 2015 | 84° | 55° | 70° | — | — |
| 2014 | 78° | 69° | 74° | 5.69" | — |
| 2013 | 90° | 66° | 78° | — | — |
| 2012 | 81° | 51° | 66° | — | — |
| 2011 | 80° | 62° | 71° | 0.05" | — |
| 2010 | 85° | 68° | 76° | — | — |
| 2009 | 71° | 59° | 65° | 0.3" | — |
| 2008 | 78° | 67° | 72° | 0.2" | — |
| 2007 | 85° | 69° | 77° | 0.05" | — |
| 2006 | 82° | 52° | 67° | — | — |
| 2005 | 80° | 61° | 70° | — | — |
| 2004 | 71° | 50° | 61° | — | — |
| 2003warmest | 98° | 71° | 85° | — | — |
| 2002 | 91° | 63° | 77° | 7.21" | — |
| 2001 | 79° | 55° | 67° | 0.08" | — |
| 2000 | 77° | 55° | 66° | — | — |
| 1999 | 78° | 52° | 65° | — | — |
| 1998 | 88° | 66° | 77° | — | — |
| 1997 | 73° | 55° | 64° | 0.03" | — |
| 1996 | 88° | 65° | 76° | 0.08" | — |
| 1995 | 87° | 64° | 76° | — | — |
| 1994 | 77° | 58° | 67° | — | — |
| 1993 | 82° | 60° | 71° | — | — |
| 1992 | 78° | 48° | 63° | — | — |
| 1991 | 86° | 56° | 71° | — | — |
| 1990 | 72° | 66° | 69° | — | — |
| 1989 | 85° | 59° | 72° | — | — |
| 1988 | 82° | 59° | 71° | — | — |
| 1987 | 86° | 66° | 76° | 1.63" | — |
| 1986 | 76° | 60° | 68° | — | — |
| 1985coldest | 74° | 48° | 61° | — | — |
| 1984 | 85° | 56° | 70° | 1.24" | — |
| 1983 | 95° | 69° | 82° | 1.14" | — |
| 1982 | 80° | 52° | 66° | — | — |
| 1981 | 81° | 51° | 66° | — | — |
| 1980 | 82° | 63° | 72° | 0.15" | — |
| 1979 | 77° | 66° | 72° | — | — |
| 1978 | 77° | 55° | 66° | — | — |
| 1977 | 73° | 57° | 65° | 0.53" | — |
| 1976 | 88° | 59° | 73° | — | — |
| 1975 | 93° | 73° | 83° | 1.22" | — |
| 1974 | 90° | 69° | 79° | — | — |
| 1973 | 76° | 56° | 66° | — | — |
| 1972 | 85° | 72° | 78° | — | — |
| 1971 | 90° | 66° | 78° | — | — |
Rockford, IL Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
Rockford, IL Monthly Precipitation
Average rainfall and snowfall per month, in inches.
Rockford, IL Daily Temperature Calendar
Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.
Best Time to Visit Rockford, IL
Rockford, IL has no months that meet our "pleasant" threshold — every season has tradeoffs.