Weather on August 18
Portland, OR
55 Years of Data
Avg High
79°F
Avg Low
58°F
Warmest
2009
78°F avg
Coldest
1975
60°F avg
About This Date
August 18th in Portland, OR typically brings pleasant summer weather, with average highs around 79°F and lows near 58°F. Over 55 years of records, the warmest August 18th was in 2009 (78°F average), while the coldest was 1975 (60°F) — a 18°F range across recorded history. Rain or other precipitation has occurred on about 13% of August 18th dates historically, with the wettest August 18th recording 0.56" of rain. The last decade has been 2.8°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.8°F warmer on this date compared to 20-30 years ago.
Planning for August 18th in Portland, OR? Great weather for outdoor activities.
Warming Trend
0.9°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 78° | 62° | 70° | — | — |
| 2024 | 75° | 59° | 67° | 0.03" | — |
| 2023 | 79° | 58° | 68° | — | — |
| 2022 | 83° | 72° | 77° | — | — |
| 2021 | 79° | 55° | 67° | — | — |
| 2020 | 81° | 61° | 71° | — | — |
| 2019 | 74° | 56° | 65° | — | — |
| 2018 | 84° | 56° | 70° | — | — |
| 2017 | 79° | 56° | 67° | — | — |
| 2016 | 95° | 61° | 78° | — | — |
| 2015 | 93° | 63° | 78° | — | — |
| 2014 | 88° | 62° | 75° | — | — |
| 2013 | 81° | 58° | 69° | — | — |
| 2012 | 78° | 60° | 69° | — | — |
| 2011 | 80° | 54° | 67° | — | — |
| 2010 | 76° | 62° | 69° | — | — |
| 2009warmest | 92° | 65° | 78° | — | — |
| 2008 | 72° | 61° | 66° | 0.56" | — |
| 2007 | 74° | 57° | 65° | — | — |
| 2006 | 90° | 58° | 74° | — | — |
| 2005 | 83° | 59° | 71° | — | — |
| 2004 | 86° | 64° | 75° | — | — |
| 2003 | 86° | 62° | 74° | — | — |
| 2002 | 81° | 54° | 67° | — | — |
| 2001 | 71° | 58° | 64° | — | — |
| 2000 | 70° | 56° | 63° | 0.38" | — |
| 1999 | 74° | 61° | 67° | — | — |
| 1998 | 71° | 53° | 62° | — | — |
| 1997 | 73° | 62° | 68° | — | — |
| 1996 | 70° | 53° | 61° | — | — |
| 1995 | 76° | 53° | 64° | — | — |
| 1994 | 80° | 57° | 69° | — | — |
| 1993 | 85° | 55° | 70° | — | — |
| 1992 | 85° | 59° | 72° | — | — |
| 1991 | 85° | 62° | 73° | 0.13" | — |
| 1990 | 76° | 57° | 66° | — | — |
| 1989 | 83° | 59° | 71° | — | — |
| 1988 | 75° | 52° | 63° | — | — |
| 1987 | 83° | 57° | 70° | — | — |
| 1986 | 78° | 56° | 67° | — | — |
| 1985 | 72° | 58° | 65° | — | — |
| 1984 | 77° | 60° | 69° | — | — |
| 1983 | 81° | 55° | 68° | — | — |
| 1982 | 84° | 58° | 71° | — | — |
| 1981 | 92° | 62° | 77° | — | — |
| 1980 | 74° | 55° | 64° | — | — |
| 1979 | 71° | 59° | 65° | 0.3" | — |
| 1978 | 76° | 58° | 67° | — | — |
| 1977 | 82° | 60° | 71° | — | — |
| 1976 | 78° | 53° | 66° | — | — |
| 1975coldest | 62° | 57° | 60° | 0.38" | — |
| 1974 | 67° | 57° | 62° | 0.15" | — |
| 1973 | 75° | 46° | 61° | — | — |
| 1972 | 82° | 54° | 68° | — | — |
| 1971 | 83° | 59° | 71° | — | — |
55 years of data from PORTLAND KGW-TV