Thanks for the reply.. So no, I am depositing physical cash. So if I deposit this Monday morning and buy from Coinbase 30 minutes later there shouldn't be a problem?
I don't want to give you bad information and it then end up costing you a lot of money in various bank fees as explained above. I don't think it will be a problem. However my recommendation is to speak to one of the bank employees, tell them that you are expecting an ACH withdrawal to be initiated in the near future and you want to confirm that funds will be available to cover the withdrawal. They might ask about pending checks that have not been presented yet and other pending withdrawals.
I don't see any reason however why it would be a problem.