Help! Lightroom Slowing down ‘wheel of death’ during develop editing!

please offer any advise to help speed up my work flow. I am currently half way into a world tour with major rock band. I am shooting 3-4000 RAW files every night on a Nikon D5 and D4s. Every 10 frames or so whilst editing I am getting the wheel of death and Lightroom is unusable. It is becoming very ncreadingly frustrating and massively effecting my work flow. The D4s RAW files on Lightroom 5 work without any delay. Lightroom CC is becoming unusable. My drive is an external Thunderbolt WD pro drive and is super fast. I am using a MacBook Pro with 16gb of RAM. Any id as how to speed things up? I used to edit a days photography in just over one hour. It is now taking me 4! Thanks

John Mc