Weather on August 21
Hillsboro, OR
55 Years of Data
Avg High
79°F
Avg Low
52°F
Warmest
2018
74°F avg
Coldest
1985
57°F avg
About This Date
August 21st in Hillsboro, OR typically brings pleasant summer weather, with average highs around 79°F and lows near 52°F — a 27°F daily swing. Over 55 years of records, the warmest August 21st was in 2018 (74°F average), while the coldest was 1985 (57°F) — a 17°F range across recorded history. Rain or other precipitation has occurred on about 20% of August 21st dates historically, with the wettest August 21st recording 1.37" of rain. The last decade has been 1.5°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.5°F warmer on this date compared to 20-30 years ago.
Planning for August 21st in Hillsboro, OR? Great weather for outdoor activities.
Warming Trend
0.8°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 90° | 50° | 70° | — | — |
| 2024 | 73° | 53° | 63° | — | — |
| 2023 | 82° | 51° | 67° | — | — |
| 2022 | 89° | 53° | 71° | — | — |
| 2021 | 70° | 53° | 61° | 0.03" | — |
| 2020 | 76° | 56° | 66° | 0.03" | — |
| 2019 | 73° | 51° | 62° | 0.05" | — |
| 2018warmest | 93° | 55° | 74° | — | — |
| 2017 | 94° | 52° | 73° | — | — |
| 2016 | 82° | 53° | 68° | — | — |
| 2015 | 80° | 52° | 66° | — | — |
| 2014 | 79° | 45° | 62° | — | — |
| 2013 | 92° | 50° | 71° | — | — |
| 2012 | 76° | 53° | 64° | — | — |
| 2011 | 90° | 54° | 72° | — | — |
| 2010 | 71° | 44° | 58° | — | — |
| 2009 | 75° | 54° | 64° | — | — |
| 2008 | 71° | 53° | 62° | 0.15" | — |
| 2007 | 78° | 59° | 69° | — | — |
| 2006 | 81° | 56° | 68° | — | — |
| 2005 | 83° | 53° | 68° | — | — |
| 2004 | 81° | 57° | 69° | 0.89" | — |
| 2003 | 89° | 51° | 70° | — | — |
| 2002 | 68° | 50° | 59° | — | — |
| 2001 | 75° | 51° | 63° | — | — |
| 2000 | 82° | 44° | 63° | — | — |
| 1999 | 78° | 55° | 67° | — | — |
| 1998 | 78° | 60° | 69° | — | — |
| 1997 | 81° | 56° | 68° | — | — |
| 1996 | 81° | 48° | 64° | — | — |
| 1995 | 81° | 51° | 66° | — | — |
| 1994 | 74° | 53° | 63° | 0.08" | — |
| 1993 | 75° | 58° | 66° | — | — |
| 1992 | 84° | 46° | 65° | — | — |
| 1991 | 93° | 53° | 73° | — | — |
| 1990 | 84° | 57° | 71° | — | — |
| 1989 | 73° | 57° | 65° | — | — |
| 1988 | 72° | 44° | 58° | — | — |
| 1987 | 76° | 46° | 61° | — | — |
| 1986 | 94° | 52° | 73° | — | — |
| 1985coldest | 71° | 43° | 57° | — | — |
| 1984 | 85° | 49° | 67° | — | — |
| 1983 | 76° | 47° | 61° | — | — |
| 1982 | 91° | 52° | 71° | — | — |
| 1981 | 72° | 48° | 60° | — | — |
| 1980 | 78° | 41° | 60° | — | — |
| 1979 | 77° | 54° | 65° | 1.37" | — |
| 1978 | 69° | 54° | 61° | 1.17" | — |
| 1977 | 68° | 60° | 64° | 0.13" | — |
| 1976 | 81° | 46° | 63° | — | — |
| 1975 | 72° | 56° | 64° | — | — |
| 1974 | 79° | 48° | 63° | — | — |
| 1973 | 76° | 43° | 59° | — | — |
| 1972 | 79° | 56° | 67° | 0.53" | — |
| 1971 | 74° | 58° | 66° | 0.15" | — |
55 years of data from HILLSBORO