Hmmm... you are running a really old PHP 5.3.3 on your site. Is it possible to upgrade to PHP 5.5 5.6 or 7.1? The old curl on 5.3.3 had a few https foibles and maybe you're having the issue there. I tried your URL+zone in the current JSON script (which you are running that version) and it worked fine. Your site is also uses ngnix for web services and not apache, but I don't think that would make a difference (but the old PHP might).
Contact the tech support for your hoster and ask them what permissions to use on the weather/cache/ directory in order to allow a PHP script to write a file there, and ask about upgrading the PHP version. Since you're not running a Saratoga template site, I don't have access to my customary diagnostic tool, so I can only use the HTML comments in the view-source of the script running to see what issues there are .. the 'unable to write' the cache file(s) is the current big issue.