Weather on May 21
Hillsboro, OR
55 Years of Data
Avg High
68°F
Avg Low
46°F
Warmest
2000
70°F avg
Coldest
2005
48°F avg
About This Date
May 21st in Hillsboro, OR typically brings mild spring weather, with average highs around 68°F and lows near 46°F. Over 55 years of records, the warmest May 21st was in 2000 (70°F average), while the coldest was 2005 (48°F) — a 22°F range across recorded history. Rain or other precipitation has occurred on about 31% of May 21st dates historically, with the wettest May 21st recording 1.27" of rain. The last decade has been 2.5°F cooler on this date compared to 20-30 years ago.
The last decade has been 2.5°F cooler on this date compared to 20-30 years ago.
Planning for May 21st in Hillsboro, OR? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.
Cooling Trend
0.5°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 68° | 40° | 54° | — | — |
| 2024 | 55° | 41° | 48° | 0.48" | — |
| 2023 | 66° | 49° | 57° | — | — |
| 2022 | 72° | 38° | 55° | — | — |
| 2021 | 67° | 38° | 52° | — | — |
| 2020 | 61° | 46° | 53° | 0.05" | — |
| 2019 | 67° | 48° | 57° | 0.08" | — |
| 2018 | 74° | 41° | 57° | — | — |
| 2017 | 83° | 50° | 66° | — | — |
| 2016 | 62° | 49° | 55° | 0.03" | — |
| 2015 | 76° | 54° | 65° | — | — |
| 2014 | 73° | 44° | 59° | — | — |
| 2013 | 58° | 44° | 51° | 0.79" | — |
| 2012 | 62° | 52° | 57° | 1.04" | — |
| 2011 | 62° | 46° | 54° | — | — |
| 2010 | 53° | 44° | 49° | 1.22" | — |
| 2009 | 74° | 40° | 57° | — | — |
| 2008 | 59° | 48° | 54° | — | — |
| 2007 | 60° | 40° | 50° | — | — |
| 2006 | 72° | 50° | 61° | 0.56" | — |
| 2005coldest | 58° | 39° | 48° | 0.28" | — |
| 2004 | 62° | 51° | 57° | — | — |
| 2003 | 66° | 50° | 58° | — | — |
| 2002 | 65° | 46° | 55° | 0.08" | — |
| 2001 | 85° | 51° | 68° | — | — |
| 2000warmest | 82° | 57° | 70° | 0.15" | — |
| 1999 | 67° | 50° | 58° | — | — |
| 1998 | 63° | 46° | 54° | — | — |
| 1997 | 70° | 49° | 59° | — | — |
| 1996 | 58° | 46° | 52° | 1.27" | — |
| 1995 | 80° | 51° | 66° | — | — |
| 1994 | 61° | 52° | 56° | — | — |
| 1993 | 74° | 54° | 64° | 0.91" | — |
| 1992 | 71° | 38° | 54° | — | — |
| 1991 | 65° | 50° | 57° | — | — |
| 1990 | 62° | 47° | 54° | 0.18" | — |
| 1989 | 71° | 42° | 57° | — | — |
| 1988 | 77° | 46° | 62° | — | — |
| 1987 | 71° | 42° | 57° | — | — |
| 1986 | 62° | 39° | 51° | — | — |
| 1985 | 63° | 43° | 53° | — | — |
| 1984 | 59° | 39° | 49° | 0.1" | — |
| 1983 | 82° | 47° | 64° | — | — |
| 1982 | 77° | 44° | 61° | — | — |
| 1981 | 63° | 48° | 55° | — | — |
| 1980 | 78° | 50° | 64° | 0.43" | — |
| 1979 | 81° | 50° | 65° | — | — |
| 1978 | 62° | 49° | 55° | — | — |
| 1977 | 68° | 51° | 60° | — | — |
| 1976 | 75° | 38° | 56° | — | — |
| 1975 | 65° | 38° | 51° | — | — |
| 1974 | 70° | 41° | 55° | — | — |
| 1973 | 75° | 36° | 55° | — | — |
| 1972 | 69° | 55° | 62° | 0.18" | — |
| 1971 | 74° | 41° | 57° | — | — |
55 years of data from HILLSBORO