He had referred me to another vet located in Auckland and via email that vet told me that I have to hibernate my tortoise as he had seen other tortoises in Europe do very well after hibernating. So for their health it was essential. I was not aware that he was not in an ideal environment since the temperatures here are currently not low enough. I recently spoke with the breeder I got Florin from and was told that all but one of his tortoises have "gone down" and he is experiencing similar temperatures.
It is very common to hibernate tortoises here in Europe and yes, they are doing very well living outside year-round. Tortoises getting sick are usually those that are kept inside (which is necessary when they are overwintered).
I know the recommended temperature for hibernation is 5°C without too much ups and downs,... But I stopped worrying about that so much. There are habitats where the temperatures hardly ever drop below 10°C and the tortoises still survive.
The last two winters were unusually warm here and the soil in my cold frame had about 12° for months, my torts still hibernated and awoke happy and healthy in spring. I don't live in a Mediterranean climate, it's much colder here, so I just make sure to keep my torts free of frost and that's it.
If accuweather is right I guess I would put him outside again to wind down in 2 weeeks or so. But I've no experience at all with a climate like yours, so I really can't give helpful advise. If your breeder has positive experiences with hibernation I would rather trust him.