If I know the current months ex-dividend date is there any way to determine the next months ex-dividend date?
Some ETFs, ETNs and funds pay monthly dividends. Not many stocks do so other than preferred stocks. Some will pay on the same date every month. Some will pay within a day or two on either side of last month's date.
Fidelity offers a screener which shows historical dividend and distribution amounts and ex-div dates:
Enter the symbol of your stock and see if it has consistently paid on the same date or if it has varied.