"Ce jour" is a formal way of saying "today" (in writing mostly), so you need to add "là" to indicate that you are not talking about this current day but that day further away.
"Ce" can mean both "this" or "that" if you don't add "ci" or "là".
"Il m'a fait une belle surprise ce jour-là." is also correct! This accepts both uk english and american english yet not any french except france one??? Quebec is much bigger than france, and has a lot more speakers, yet invalid here!