yr.no is the only one that I've found that really does cloud coverage well. https://www.yr.no/en/details/graph/2-4887398/United%20States/Illinois/Cook/Chicago

yr.no is the only one that I've found that really does cloud coverage well. https://www.yr.no/en/details/graph/2-4887398/United%20States/Illinois/Cook/Chicago https://www.yr.no/en/details/graph/2-4887398/United%20States... https://www.yr.no/en/details/table/2-4887398/United%20States/Illinois/Cook/Chicago https://www.yr.no/en/details/table/2-4887398/United%20States... You'll note not only cloud cover %, but fog, low, middle, and high level cloud amounts. The API is documented https://developer.yr.no https://developer.yr.no https://api.met.no/weatherapi/locationforecast/2.0/compact?lat=41.8&lon=87.6 https://api.met.no/weatherapi/locationforecast/2.0/compact?l...