I have week to week custody of my 2 children with my ex husband. He informed me his is moving over 60 miles away and wants to file for primary custody

Of course I don't know all the circumstances, but becuase you have primary custody at present, then it's going to be difficult for your ex to change that in court. If the kids are settled in school and have a stable life it would be even more unlikely to me that a judge would would change primary care unless something is wrong with the current situation.