Records for Hillsboro Area, Oregon (HIOthr) on 12-20
  Record Highs
  
    - 
      1:  61°F (1974)
    
- 
      2:  58°F (1972)
    
- 
      3:  57°F (2014)
    
 
  Record Lows
  
    - 
      1:  13°F (1998)
    
- 
      2:  13°F (1990)
    
- 
      3:  15°F (1984)
    
 
  Lowest Highs
  
    - 
      1:  51°F (1972)
    
- 
      2:  50°F (2019)
    
- 
      3:  49°F (1974)
    
 
  Highest Lows
  
    - 
      1:  25°F (1998)
    
- 
      2:  27°F (1990)
    
- 
      3:  30°F (2008)
    
 
  Highest December temperature:
  
  64°F on 12-01-1951.
  Lowest December temperature:
  
  -2°F on 12-08-1972.
  Average temperature is 39.2°F
  Average high is 45.5°F
  Average low is 32.9°F
 
  Temperature data from 1929 to 2022.
  Record Precipitation
  
    - 
      1:  1.40" (1964)
    
- 
      2:  1.30" (1955)
    
- 
      3:  1.26" (1982)
    
 
  Precipitation data from 1929 to 2022.