which way the wind is blowing

• how the wind is blowing
• what way the wind is blowing

which way the wind is blowing

1. (idiomatic) The prevailing opinion or current view of most people, especially people with influence.
   • 1975 June 29, Robert F. Lucid, "The Major Novelists View the American Businessman," New York Times (retrieved 5 Nov 2017):

     Minor writers, seeking a fashion to follow, may praise or blame various groups pretty much according to which way the wind is blowing, but the work of a writer like Ernest Hemingway, most people would agree, goes its own way.

   • 2007 October 3, Kenneth Baer and Jeff Nussbaum , "When Candidates Attack," Time (retrieved 5 Nov 2017):

     "There are folks who will shift positions and policies on all kinds of things depending on which way the wind is blowing," he told the crowd.

   • 2011 November 29, John Vidal , "Kyoto protocol may suffer fate of Julius Caesar at Durban climate talks ," Guardian (UK) (retrieved 5 Nov 2017):

     The reality of international diplomacy is that, like the senators in Julius Caesar, countries follow power, hide their weapons, watch which way the wind is blowing, and then back who they expect to be the winner.

• Often used in contexts suggesting the changeability of popular trends.

• public opinion
• you don't need a weatherman to know which way the wind blows