How can I know (without going to the station) if RTAP is offering the Anti Pollution tickets?


The Paris public transit system (RTAP) offers a reduced fare on days of high pollution, as described here: https://www.ratp.fr/forfait-antipollution (Google Translated).

This fare is a very good deal, especially as a tourist!

It has been offered so far every day that I have been visiting, but I only know that because I have been to the train station and seen it advertised. Is there a website where I can look to see whether a particular day is an anti pollution day?