It was x5.6 for the Texas Bowl, so I'm going to say it will hit at least x8.
http://blog.chron.com/thehighwayman/2014/12/almost-250-for-13-miles-ubers-surge-pricing/
http://blog.chron.com/thehighwayman/2014/12/almost-250-for-13-miles-ubers-surge-pricing/