Weather on August 18
Sioux Falls, SD
55 Years of Data
Avg High
83°F
Avg Low
60°F
Warmest
1976
87°F avg
Coldest
1997
59°F avg
About This Date
August 18th in Sioux Falls, SD typically brings warm summer weather, with average highs around 83°F and lows near 60°F. Over 55 years of records, the warmest August 18th was in 1976 (87°F average), while the coldest was 1997 (59°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 33% of August 18th dates historically, with the wettest August 18th recording 3.48" of rain. The last decade has been 5.6°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.6°F warmer on this date compared to 20-30 years ago.
Planning for August 18th in Sioux Falls, SD? Stay hydrated and seek shade during peak afternoon hours. Consider bringing rain gear or an umbrella.
Cooling Trend
0.5°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 86° | 68° | 77° | 3.48" | — |
| 2024 | 83° | 58° | 70° | — | — |
| 2023 | 84° | 57° | 71° | — | — |
| 2022 | 89° | 66° | 78° | — | — |
| 2021 | 89° | 71° | 80° | — | — |
| 2020 | 86° | 54° | 70° | — | — |
| 2019 | 74° | 59° | 66° | — | — |
| 2018 | 82° | 61° | 71° | — | — |
| 2017 | 81° | 60° | 70° | 0.18" | — |
| 2016 | 92° | 67° | 79° | — | — |
| 2015 | 68° | 52° | 60° | 2.51" | — |
| 2014 | 88° | 63° | 75° | — | — |
| 2013 | 80° | 61° | 70° | — | — |
| 2012 | 72° | 53° | 62° | 2.01" | — |
| 2011 | 80° | 63° | 71° | 0.28" | — |
| 2010 | 81° | 63° | 72° | — | — |
| 2009 | 79° | 51° | 65° | — | — |
| 2008 | 86° | 65° | 75° | — | — |
| 2007 | 86° | 61° | 73° | 1.68" | — |
| 2006 | 80° | 64° | 72° | 0.48" | — |
| 2005 | 84° | 62° | 73° | 1.02" | — |
| 2004 | 79° | 47° | 63° | — | — |
| 2003 | 92° | 73° | 82° | — | — |
| 2002 | 73° | 44° | 59° | — | — |
| 2001 | 75° | 54° | 64° | — | — |
| 2000 | 75° | 49° | 62° | — | — |
| 1999 | 80° | 56° | 68° | — | — |
| 1998 | 85° | 72° | 78° | — | — |
| 1997coldest | 69° | 48° | 59° | — | — |
| 1996 | 76° | 61° | 68° | — | — |
| 1995 | 96° | 69° | 83° | 0.28" | — |
| 1994 | 86° | 63° | 74° | — | — |
| 1993 | 80° | 67° | 73° | 1.22" | — |
| 1992 | 77° | 53° | 65° | — | — |
| 1991 | 80° | 58° | 69° | — | — |
| 1990 | 91° | 64° | 78° | 0.1" | — |
| 1989 | 83° | 61° | 72° | — | — |
| 1988 | 83° | 61° | 72° | — | — |
| 1987 | 77° | 51° | 64° | — | — |
| 1986 | 81° | 57° | 69° | 0.13" | — |
| 1985 | 72° | 48° | 60° | — | — |
| 1984 | 84° | 63° | 73° | — | — |
| 1983 | 101° | 69° | 85° | — | — |
| 1982 | 84° | 69° | 77° | — | — |
| 1981 | 75° | 48° | 62° | — | — |
| 1980 | 86° | 60° | 73° | 0.05" | — |
| 1979 | 84° | 61° | 72° | 0.56" | — |
| 1978 | 70° | 56° | 63° | 0.03" | — |
| 1977 | 70° | 53° | 61° | 0.1" | — |
| 1976warmest | 98° | 75° | 87° | — | — |
| 1975 | 74° | 56° | 65° | — | — |
| 1974 | 90° | 54° | 72° | — | — |
| 1973 | 94° | 74° | 84° | 0.23" | — |
| 1972 | 95° | 69° | 82° | — | — |
| 1971 | 97° | 68° | 82° | 0.71" | — |
55 years of data from SIOUX FALLS