I'm from Kerala, India. For the past few months, whenever I ask Cortana, "will it rain today?", Cortana displays the weather of Mumbai, India which is about 1700km away from my place and gives me wrong information. Even it's raining heavily in my place, it says "rain is unlikely". But when I ask her, "where am I now?", it displays my correct location. I'm using Lumia 830. The same problem is there in my wife's 730 also.