The expression “a storm in a teacup,” is used as a metaphor in English and does not directly relate, as one may imagine, to the weather.
The expression is used to denote a small incident which has been blown out of proportion and exaggerated. In general it is used when someone is unnecessarily angry or worried about something.
The expression “storm in a teacup,” is relevant to British English, however, American English uses the slightly different variant of “a tempest in a teapot.” The expression can be traced back to the Latin “excitabat enim fluctus in simpulo ut dicitur Gratidius,” translated as, “for Gratidius raised a tempest in a ladle, as the saying is.” The expression did not, however, begun to be used in the current form until 1815 when Britain’s Lord Chancellor Thurlow referred to an uprising on the Isle of Mann as “a tempest in a teapot.” It was then in 1838 that the British English version “a storm in a teacup,” was first used in Catherine Sinclair’s Modern Accomplishments. Throughout history it can be found in other forms such as “a storm in a wash-basin,” but the most frequently used remains “a storm in a teacup.”
An example of this expression can be found in the headline of an article on the BBC news website from March 2012 which reads “Google privacy row: storm in a teacup?” The article goes on to explore whether the change in Google’s policy is really as extreme as it has been made out and thus whether people have blown it out of proportion.