Yes. It appears Open Weather Map IS under the hood of the Codebuffer implementation.
I think I missed that as it uses the Acronym OWM. 
However ,the Codebuffer method really makes it a Click next- Add details and information to achieve a useable Weather Tile from URL.
Simple to understand questions and an automated web based form to create a Weather Tile. One can even customize the background color of the Weather tile to match thier dashboard colors. I used a Hex Color picker from the web to sample the current colors of my Dashboard icons. Found here - https://imagecolorpicker.com/
Additionally one can single press/click the Custom Weather tile and it toggles to a 4 Day Weather Forecast view. Then another press / click to toggle back.
I setup the Open Weather Weather tile using the instructions from the post here - Weather Tile - Open Weather - Current and Forecast .
I think I screwed up by editing the tile in Developer Mode - I added Latitude and Longitude as well as possibly other details. I notice that the instructions state not to do that. In any case I ended up with a tile that was bright blue and had yellow lettering for the icons/images. This was far from my desired color scheme, but decided to run with it for a day or two to observe its behavior and that’s when I found that it was not updating the weather data at regular pre-defined intervals.
I scraped the idea of using OWM for weather reporting after this.
The codebuffer method makes it simpler to achieve a weather tile that can be used within one’s dashboard . At least to my brain it does.