Weather on August 31
Portland, OR
55 Years of Data
Avg High
77°F
Avg Low
57°F
Warmest
1987
86°F avg
Coldest
2008
56°F avg
About This Date
August 31st in Portland, OR typically brings pleasant summer weather, with average highs around 77°F and lows near 57°F. Over 55 years of records, the warmest August 31st was in 1987 (86°F average), while the coldest was 2008 (56°F) — a 30°F range across recorded history. Rain or other precipitation has occurred on about 16% of August 31st dates historically, with the wettest August 31st recording 1.37" 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 31st in Portland, OR? Great weather for outdoor activities.
Warming Trend
0.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 80° | 60° | 70° | — | — |
| 2024 | 97° | 60° | 78° | — | — |
| 2023 | 65° | 59° | 62° | 1.37" | — |
| 2022 | 91° | 64° | 78° | — | — |
| 2021 | 67° | 51° | 59° | — | — |
| 2020 | 73° | 59° | 66° | — | — |
| 2019 | 83° | 59° | 71° | — | — |
| 2018 | 73° | 58° | 65° | — | — |
| 2017 | 80° | 62° | 71° | — | — |
| 2016 | 68° | 58° | 63° | — | — |
| 2015 | 72° | 58° | 65° | — | — |
| 2014 | 75° | 57° | 66° | — | — |
| 2013 | 89° | 60° | 75° | — | — |
| 2012 | 76° | 55° | 65° | — | — |
| 2011 | 71° | 54° | 62° | — | — |
| 2010 | 64° | 55° | 60° | 0.48" | — |
| 2009 | 81° | 59° | 70° | — | — |
| 2008coldest | 64° | 49° | 56° | 0.15" | — |
| 2007 | 77° | 59° | 68° | — | — |
| 2006 | 78° | 50° | 64° | — | — |
| 2005 | 79° | 57° | 68° | — | — |
| 2004 | 85° | 62° | 73° | — | — |
| 2003 | 82° | 57° | 70° | — | — |
| 2002 | 82° | 57° | 70° | — | — |
| 2001 | 78° | 60° | 69° | — | — |
| 2000 | 69° | 57° | 63° | — | — |
| 1999 | 66° | 52° | 59° | 0.1" | — |
| 1998 | 96° | 64° | 80° | — | — |
| 1997 | 81° | 55° | 68° | — | — |
| 1996 | 75° | 60° | 68° | — | — |
| 1995 | 86° | 57° | 72° | — | — |
| 1994 | 83° | 57° | 70° | — | — |
| 1993 | 85° | 59° | 72° | — | — |
| 1992 | 72° | 58° | 65° | — | — |
| 1991 | 67° | 58° | 62° | 0.33" | — |
| 1990 | 76° | 55° | 65° | — | — |
| 1989 | 71° | 58° | 64° | — | — |
| 1988 | 83° | 55° | 69° | — | — |
| 1987warmest | 101° | 72° | 86° | — | — |
| 1986 | 75° | 57° | 66° | — | — |
| 1985 | 74° | 51° | 62° | — | — |
| 1984 | 68° | 57° | 63° | 0.2" | — |
| 1983 | 75° | 60° | 68° | 0.18" | — |
| 1982 | 76° | 54° | 65° | — | — |
| 1981 | 78° | 58° | 68° | — | — |
| 1980 | 71° | 56° | 63° | 0.03" | — |
| 1979 | 81° | 61° | 71° | — | — |
| 1978 | 75° | 61° | 68° | — | — |
| 1977 | 74° | 52° | 63° | — | — |
| 1976 | 85° | 60° | 72° | — | — |
| 1975 | 70° | 50° | 60° | — | — |
| 1974 | 77° | 61° | 69° | — | — |
| 1973 | 68° | 48° | 58° | — | — |
| 1972 | 86° | 58° | 72° | — | — |
| 1971 | 64° | 56° | 60° | 0.18" | — |
55 years of data from PORTLAND KGW-TV