From Longman Dictionary of Contemporary Englisha storm in a teacupa storm in a teacupBritish EnglishUNIMPORTANT an unnecessary expression of strong feelings about something that is very unimportant → storm
Examples from the Corpus
a storm in a teacup• Both are trying to present the disagreement as a storm in a teacup.• Others sink in what outsiders might regard as a storm in a teacup.• But Mr Tait described the row as a storm in a teacup.• Within Dotty's hearing a home pirate remarked that he thought it had all been a storm in a teacup.• The succession issue seems rather a storm in a teacup to me.• However, it's a storm in a teacup. 