I think you could just pick the series up with Midnight Tides... it's a great story, and overall rather independent from the previous books. But there is an overarcing story starting to build up, from somewhere around book 3;
The story of the Crippled God.
On that front, you'll be a bit lost... but it can still probably be done.
If you enjoy it, though, I'd recommend diving back into the whole series at some point. It's hard, but I think it's worse if you pause between books and forget the details (it is a huge
world and a huge plot, one of the more confusing I've read).