How to cancel the weather forecast harassing SMS?

You can't cancel this short message through 10086, because this is the code of a telecom operator, so you should see if there are any other clues in the short message, such as contact number. If not, you can directly complain to the communication administration of your city and ask them to solve it, or you can call Mobile and ask them to blacklist you, and you will never receive this kind of short message again.