When you go into cPanel, open the File Manager and write down the path as you discover it. First, at the top of the upper left hand corner you will see:
/home/GoDaddy's alpha-numeric ID which is specific to your site/
Then you click on public_html to expand it.
Now you need to go through the sub folders until you find the one where you are uploading your weather data. Like Edouard, mine is called Weather. However, I created that folder in File Manager. I don't know if you created yours, or if GoDaddy created it, or if your data is just being uploaded to the root of public_html without being in a separate folder, where it should be.
When you find the data, you will then know your full path for FTP. It should be similar to what Edouard used in his example:
/home/GoDaddy's alpha-numeric ID which is specific to your site/public_html/whatever folder you are uploading your weather data to/
Once you know that path, you need to create an FTP account in cPanel, to that path. You do that in FTP Accounts. You cannot change the path of one you have already created, you have to create a new account with the correct path.
Once you have done that, you need to make sure you are using the same FTP User Name and Password in WeatherCat for the account you just set up in cPanel.
Since your WeatherCat FTP Test looks fine, I assume the problem is that your cPanel FTP account is using the wrong path.
Hope this help.