http://en.wikipedia.org/wiki/Dubrovnik#ClimateWiki has a thing called Climate for almost any city in the world.
Typical Mediterranean climate, somewhat warm for European standards in the summer, but not Texas hot, and then mild in the winter.
My wife said that she was there about 15 years ago and the road from Split to Dubrovnik had no rail on the Adriatic side of the road and was only about 1.5 cars wide, she saw more than one car half way down the several 100 meter (yard) cliffs. She suggested not driving yourself under any circumstances, also you have to be cautious of car thieves, most rental companies wont allow you to drive a car from Italy, Austria or Germany to Croatia, Serbia or Bosnia.
I dont think that you would have to worry that much about it being a Slavic place, you just dont need to draw attention to yourselves, which is a learned practice. I figure there is no issue as long as you are quiet, dont speak English around groups of strangers and dont act outlandish. I was at the grocery store the other day and there was a group of 2 Americans and 1 brit behind me in line, I almost turned around and asked them if they felt the need to speak with the entire store, or if it would be sufficient to speak with each other, you couldnt miss hearing them no matter where you were in the store. Most of the time that isnt really a problem, its just annoying, but it does draw sometimes unwanted attention to yourselves.
Turkey will be the same in that regard and they will want you to buy whatever crap that they have at their stand in the bazaar (just firmly say no and keep walking), you just need to watch out for groups of children (pickpockets), dont draw attention to yourself with your voice level or expensive things like jewelry or cameras etc.