Sorry you’re in that muggy heat. We are enjoying the coolest week all summer, under 90 all week. It is magnificent. Even in the low 70s in the evening.
The celeriac: I know it well. When I lived in Switzerland many restaurant suppers came with a salad of julienned carrots next to one of julienned celeriac. I had no idea what it was at first. They usually had very little mayo, just enough to give it a slight flavor. I grew quite used to these standard median fare salads.
We’ve actually had a pretty good summer, after a couple of weeks of heat last month. The problem is that little thunderstorms come, and turn the ground heat into humidity - and fog. Yesterday was very foggy.
The problem with celeriac is peeling it. Once you’ve got that down, you’re home free.