Is there a way to convert Hpa to inHg? Not seeing an element that does that or an option for inHg in settings. And for my purposes Hpa is definitely not useful.
The ratio between the units hPa to height Hg is a fixed constant.
for hPa to in Hg, the factor is 2.95299830715E-2
So, add a Text layer. Open the Advanced tab for this layer ( little rocket symbol bottom right) and in the text field ( top field of Advance tab ) paste the following expression:
I hope that helps.