So I crafted the normal northern wind before, found the formula for the advanced version of it at a herbalist in Skellige, bought it but can't craft it. It just doesn't appear in the alchemy menu.

You're not the only one who's had that problem with that recipe, and others besides. This and Moon Dust; the enhanced recipes seem to be broken.

Same exact thing happened to me. bought enhanced northern wind from skellige herbalist and it doesn't appear in my alchemical formula list

Try discarding the base northern wind that you already crafted. That usually puts both recipes back in your inventory. If it works you will have to craft the regular and enhanced at the same time, or it might hide both recipes again.

Have tested, it works; hope the bug doesn't rise again with superior-level NW/MD.

This has happened to me too. Annoying <.<

Hopefully they fix in the next patch.

Can also tell you (at least with Moon Dust, presumably Northern Wind as well) that the glitch also occurs when trying to upgrade it to the superior level. It's like the first level is given higher priority than the other two.

(So instead of "superior overwrites enhanced overwrites standard", in this case "standard overwrites superior overwrites enhanced")

Thanks for the info on workaround (hope they'll fix the recepie bugs soon)!