As it stands, WeatherAds is a demand-side tool, and is integrated with AdWords, Facebook and Instagram allowing users to easily set up weather based automation for their search, display, social and shopping campaigns.
At the moment you cannot use WeatherAds with a supply side platform, or indeed as a direct integration with your own website CMS.
Therefor WeatherAds won't work if you are looking to trigger ads based on weather across your own website or eCommerce store, or your network of publisher sites (if you are an ad network running an SSP).