My wife is the queen of command strips for all kinds of things but for flat mounting velcro is my go to.

velcro

I've actually found screws don't hold too bad on our thin wallboard as long as I don't over tighten to the point they lose their bite.
Added this shelf years ago and it's still there! https://www.loveyourrv.com/extra-rv-shelving-mod-towels-linens/ and my weather station display is hung on screws, but it has two.
For things, I don't need to remove easily I use 3M outside mounting tape - https://www.loveyourrv.com/attaching-decor-rv-walls-without-screws/
Another option is Well-Nuts

Picked up a roll of Nano tape seems to work quite well and it is reusable.

I have had great luck with the Velcro type command strips. I prefer the newer type Velcro which has sort of a mushroom shaped (pin head) attachment on BOTH strips. I think they call them picture hangers.

The display should be easily in their weight range.

One thing on command strips is that they will stick to the cheap RV wallpaper better than the wallpaper will stick to the actual wall. I had a hook holding a small cutting board to my kitchen wall. One time I went to use it and noticed it was swinging on a large bubble of wallpaper. I had to carefully remove the command strip, slice the wallpaper bubble, and add glue under the wallpaper to get it to lay back down.

FYI

Hey, everybody! Thanks for the suggestions which led me to decide using a Hollow Door Anchor & it worked like a charm. I made a small wooden wedge for the back so the weather station stays firmly in place while underway.
(On a related note, The picture above is a little box frame from a Dollar Store. I put a pic I like in, (It’s actually a napkin....coolest ever!), then jerry-rigged it to easily remove & fit perfectly over the display before bed. Even at its lowest setting, the light from the display annoyingly flooded the whole rig. Problem solved!)