very bad weather in region. It's only 16 C in Belgrade!
Yes, it's very cold. Not good for playing tennis at all. All of Slovenia is cold (they are promising snow under 1500 m tomorrow) and rainy (until Tuesday, if we believe it, then it will just be cold). But Portorož is usually a bit better, because it's by the sea...
It seems a bad idea now, but they really couldn't predict such a bad weather. It's not like it's Wimbledon . Usually September here is very nice and warm, but this year there was rain the whole summer (maybe 3-4 weeks of sun spread out over 4 months).
Not using covered courts (they do have at least two with the same surface) was a very bad idea, though (I think they converted those courts into press center for the tournament, at least that was the intention before the start ).