Wikipedia does not currently have an article on "snow day", but our sister project Wiktionary does:

Read the Wiktionary entry on "snow day"

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• Search for Snow day (meteorology) in Wikipedia to check for alternative titles or spellings.
• Start the Snow day (meteorology) article, using the Article Wizard if you wish, or add a request for it; but please remember that Wikipedia is not a dictionary.
  wiktionary:snow day