Can you make your weather API send out the data in JSON instead of XML? Many can if you specify an additional option when you request the data.
Then you can use my JSON Parser to extract the bits of data you want. It’s designed to work with the chunked responses you get from a webhook when the data is spread across multiple responses. And there’s a handy tool that you paste in the JSON and then click on an item and it will generate the code you need to extract that item from the data structure.