Weather on August 20
Boise, ID
55 Years of Data
Avg High
89°F
Avg Low
59°F
Warmest
1977
83°F avg
Coldest
1974
61°F avg
About This Date
August 20th in Boise, ID typically brings warm summer weather, with average highs around 89°F and lows near 59°F — a 30°F daily swing. Over 55 years of records, the warmest August 20th was in 1977 (83°F average), while the coldest was 1974 (61°F) — a 22°F range across recorded history. Rain or other precipitation has occurred on about 9% of August 20th dates historically. 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 20th in Boise, ID? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
1.2°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 93° | 63° | 78° | — | — |
| 2024 | 90° | 60° | 75° | — | — |
| 2023 | 77° | 69° | 73° | 0.05" | — |
| 2022 | 96° | 68° | 82° | — | — |
| 2021 | 85° | 56° | 70° | — | — |
| 2020 | 91° | 67° | 79° | — | — |
| 2019 | 98° | 64° | 81° | — | — |
| 2018 | 90° | 62° | 76° | — | — |
| 2017 | 86° | 54° | 70° | — | — |
| 2016 | 91° | 59° | 75° | — | — |
| 2015 | 92° | 61° | 76° | — | — |
| 2014 | 86° | 65° | 75° | — | — |
| 2013 | 96° | 60° | 78° | — | — |
| 2012 | 95° | 64° | 80° | — | — |
| 2011 | 93° | 55° | 74° | — | — |
| 2010 | 95° | 60° | 78° | — | — |
| 2009 | 99° | 68° | 83° | — | — |
| 2008 | 89° | 63° | 76° | — | — |
| 2007 | 86° | 52° | 69° | — | — |
| 2006 | 93° | 57° | 75° | — | — |
| 2005 | 98° | 66° | 82° | — | — |
| 2004 | 90° | 63° | 76° | — | — |
| 2003 | 92° | 63° | 77° | — | — |
| 2002 | 81° | 60° | 70° | — | — |
| 2001 | 90° | 57° | 73° | — | — |
| 2000 | 78° | 53° | 66° | — | — |
| 1999 | 98° | 62° | 80° | — | — |
| 1998 | 95° | 61° | 78° | — | — |
| 1997 | 100° | 66° | 83° | — | — |
| 1996 | 84° | 56° | 70° | — | — |
| 1995 | 98° | 55° | 77° | — | — |
| 1994 | 90° | 54° | 72° | — | — |
| 1993 | 84° | 63° | 73° | — | — |
| 1992 | 96° | 60° | 78° | — | — |
| 1991 | 96° | 67° | 81° | — | — |
| 1990 | 74° | 52° | 63° | 0.36" | — |
| 1989 | 83° | 52° | 67° | — | — |
| 1988 | 84° | 52° | 68° | — | — |
| 1987 | 89° | 53° | 71° | — | — |
| 1986 | 95° | 59° | 77° | — | — |
| 1985 | 85° | 52° | 68° | — | — |
| 1984 | 82° | 46° | 64° | — | — |
| 1983 | 82° | 59° | 71° | — | — |
| 1982 | 95° | 64° | 80° | 0.05" | — |
| 1981 | 88° | 58° | 73° | 0.03" | — |
| 1980 | 84° | 51° | 68° | — | — |
| 1979 | 84° | 54° | 69° | — | — |
| 1978 | 89° | 52° | 70° | — | — |
| 1977warmest | 96° | 70° | 83° | — | — |
| 1976 | 90° | 57° | 73° | — | — |
| 1975 | 75° | 55° | 65° | — | — |
| 1974coldest | 73° | 49° | 61° | 0.15" | — |
| 1973 | 95° | 60° | 78° | — | — |
| 1972 | 89° | 55° | 72° | — | — |
| 1971 | 91° | 67° | 79° | — | — |
55 years of data from BOISE AIR TERMINAL