That might depend upon the city, industry and your skill set if you think about it. I'm sure if you had some rare in demand skill and are based in silicon valley that people might pouch you at 1am at a bar if met the HR person by accident. By the way an argument for job hunting at a bad time is that you have a higher chance of getting a better job if the pool of applicants is smaller...
August and November 20 through the end of the year are bad times.