Records for Great Falls Area, Montana (GTFthr) on 05-21
  Record Highs
  
    - 
      1:  93°F (1980)
    
- 
      2:  89°F (1928)
    
- 
      3:  88°F (1967)
    
 
  Record Lows
  
    - 
      1:  24°F (2022)
    
- 
      2:  26°F (2021)
    
- 
      3:  30°F (2009)
    
 
  Lowest Highs
  
    - 
      1:  63°F (1925)
    
- 
      2:  56°F (1966)
    
- 
      3:  55°F (2012)
    
 
  Highest Lows
  
    - 
      1:  30°F (2021)
    
- 
      2:  45°F (1987)
    
- 
      3:  46°F (1974)
    
 
  Highest May temperature:
  
  100°F on 05-28-1919.
  Lowest May temperature:
  
  12°F on 05-01-2009.
  Average temperature is 55.8°F
  Average high is 68.1°F
  Average low is 43.5°F
 
  Temperature data from 1891 to 2022.
  Record Precipitation
  
    - 
      1:  1.43" (1962)
    
- 
      2:  1.13" (1927)
    
- 
      3:  0.85" (1893)
    
 
  Precipitation data from 1891 to 2022.