Records for Rapid City Area, South Dakota (RAPthr) on 08-21
  Record Highs
  
    - 
      1:  101°F (1947)
    
- 
      2:  99°F (2010)
    
- 
      3:  99°F (1962)
    
 
  Record Lows
  
    - 
      1:  43°F (2021)
    
- 
      2:  44°F (2016)
    
- 
      3:  44°F (1966)
    
 
  Lowest Highs
  
    - 
      1:  67°F (1947)
    
- 
      2:  66°F (1988)
    
- 
      3:  66°F (1983)
    
 
  Highest Lows
  
    - 
      1:  60°F (1964)
    
- 
      2:  64°F (1966)
    
- 
      3:  66°F (2018)
    
 
  Highest August temperature:
  
  107°F on 08-13-2007.
  Lowest August temperature:
  
  37°F on 08-31-2020.
  Average temperature is 71°F
  Average high is 82.8°F
  Average low is 59.1°F
 
  Temperature data from 1942 to 2022.
  Record Precipitation
  
    - 
      1:  0.92" (1964)
    
- 
      2:  0.60" (1983)
    
- 
      3:  0.36" (1961)
    
 
  Precipitation data from 1942 to 2022.