Weather on December 18
Hillsboro, OR
55 Years of Data
Avg High
46°F
Avg Low
34°F
Warmest
1999
54°F avg
Coldest
2006
28°F avg
About This Date
December 18th in Hillsboro, OR typically brings chilly winter weather, with average highs around 46°F and lows near 34°F. Over 55 years of records, the warmest December 18th was in 1999 (54°F average), while the coldest was 2006 (28°F) — a 26°F range across recorded history. Rain or other precipitation has occurred on about 62% of December 18th dates historically, with the wettest December 18th recording 5" of rain. The last decade has been 4.1°F warmer on this date compared to 20-30 years ago.
The last decade has been 4.1°F warmer on this date compared to 20-30 years ago.
Planning for December 18th in Hillsboro, OR? Bring layers as temperatures can vary throughout the day. Consider bringing rain gear or an umbrella.
Warming Trend
0.3°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 57° | 42° | 50° | 5" | — |
| 2024 | 58° | 42° | 50° | 0.48" | — |
| 2023 | 48° | 37° | 43° | 0.08" | — |
| 2022 | 45° | 34° | 39° | 0.08" | — |
| 2021 | 50° | 35° | 43° | 2.64" | — |
| 2020 | 50° | 38° | 44° | 0.43" | — |
| 2019 | 42° | 29° | 36° | 0.3" | — |
| 2018 | 56° | 42° | 49° | 2.29" | — |
| 2017 | 51° | 45° | 48° | 0.03" | — |
| 2016 | 36° | 23° | 30° | — | — |
| 2015 | 52° | 39° | 45° | 0.58" | — |
| 2014 | 51° | 43° | 47° | 0.58" | — |
| 2013 | 40° | 25° | 33° | 0.05" | — |
| 2012 | 40° | 34° | 37° | 0.2" | — |
| 2011 | 42° | 35° | 39° | — | — |
| 2010 | 46° | 35° | 41° | 0.61" | — |
| 2009 | 50° | 33° | 42° | — | — |
| 2008 | 38° | 26° | 32° | 0.25" | — |
| 2007 | 50° | 40° | 45° | 0.99" | — |
| 2006coldest | 32° | 24° | 28° | — | — |
| 2005 | 35° | 29° | 32° | 0.03" | — |
| 2004 | 54° | 34° | 44° | — | — |
| 2003 | 52° | 32° | 42° | — | — |
| 2002 | 46° | 38° | 42° | 0.53" | — |
| 2001 | 45° | 32° | 38° | 0.41" | — |
| 2000 | 46° | 27° | 36° | — | — |
| 1999warmest | 60° | 49° | 54° | — | — |
| 1998 | 44° | 27° | 35° | — | — |
| 1997 | 37° | 33° | 35° | 0.3" | — |
| 1996 | 40° | 27° | 33° | — | — |
| 1995 | 42° | 38° | 40° | 1.27" | — |
| 1994 | 56° | 45° | 50° | 0.23" | — |
| 1993 | 46° | 26° | 36° | — | — |
| 1992 | 41° | 28° | 35° | 0.46" | — |
| 1991 | 41° | 29° | 35° | 0.61" | — |
| 1990 | 51° | 42° | 47° | 0.05" | — |
| 1989 | 32° | 28° | 30° | — | — |
| 1988 | 51° | 23° | 37° | — | — |
| 1987 | 43° | 29° | 36° | — | — |
| 1986 | 47° | 28° | 37° | — | — |
| 1985 | 46° | 23° | 35° | — | — |
| 1984 | 38° | 24° | 31° | — | — |
| 1983 | 41° | 33° | 37° | — | — |
| 1982 | 47° | 40° | 43° | 0.81" | — |
| 1981 | 47° | 40° | 43° | 0.38" | — |
| 1980 | 49° | 37° | 43° | 0.13" | — |
| 1979 | 55° | 40° | 47° | 1.75" | — |
| 1978 | 35° | 29° | 32° | — | — |
| 1977 | 46° | 36° | 41° | 0.23" | — |
| 1976 | 43° | 39° | 41° | — | — |
| 1975 | 52° | 29° | 40° | 0.03" | — |
| 1974 | 54° | 36° | 45° | 0.99" | — |
| 1973 | 55° | 39° | 47° | 0.03" | — |
| 1972 | 55° | 36° | 45° | 2.29" | — |
| 1971 | 48° | 41° | 45° | — | — |
55 years of data from HILLSBORO