I created an Home Assistant sensor for METAR temperatures https://en.wikipedia.org/wiki/METAR.
Because I use Prometheus and I also wrote an exporter for METAR.
I was inspired by the Home Assistant Command Line Sensor so instead to write code two times I decided to create sensor to use PromQL queries to retrieve Prometheus data.
You can find here https://github.com/lfasci/homeassistant-prometheus-query.
Hope this helps, feel free to fork it