nightmare vs tempest

nightmare

noun
  • Any bad, miserable, difficult or terrifying situation or experience that arouses anxiety, terror, agony or great displeasure. 

  • A very bad or frightening dream. 

  • A feeling of extreme anxiety or suffocation experienced during sleep; Sleep paralysis. 

verb
  • To have a nightmare. 

tempest

noun
  • Any violent tumult or commotion. 

  • A storm, especially one with severe winds. 

verb
  • To storm. 

  • To disturb, as by a tempest. 

How often have the words nightmare and tempest occurred in a corpus of books? (source: Google Ngram Viewer )