I suppose Sydney gets very hot. It was NYE that it reached 43 I believe, as it almost did in Melbourne too. But most of the time it seems closer to 30 degrees, but with high humidity. Ever so high humidity. Of course if you are near the harbour, there is nearly always a cool breeze to stand in and try to dry your skin.
When we took the o/s rels to Manly on the ferry, it never occured to us that the harbour would not be sparkling blue. Instead it was grey, with a strong cool wind blowing. We did not expect it to softly rain while we were in Manly, but it did.
It also never occured to us that in the middle of summer, the Three Sisters in the Blue Mountains would be shrouded in mist and invisible. It did give the rain forest an authentic feel though. It never occured to us that mist would be all you could see from some of the wonderful lookouts in the Blue Mountains.
While Melbourne's weather is extreme and changeable, it is not quite as weird as Sydney's weather.