It's funny how this is posted two days after I finished my Weather web app which uses Dark Sky's free API:
https://weather-dj.netlify.app/
Let's hope that in the future Apple continues to deliver the same API structure as Dark Sky did, because it will be a big shame if they did some changes or limitations to it. Although I only use this app mostly for my personal use, the effort that I've put into this would be for nothing's worth.