I like to use thermometers in different places to get ambient temps and humidity. I use the ones that go into the enclosure vs. the ones like you have with a probe. I put them all over, one on the cool end, one on the warm end, and one in the middle just so I can see what my gradient looks like throughout the day. I also periodically IR temp gun surfaces just to verify that everything is working the way I want it to.
I like to move my thermometers around as well, put them at floor level, on top of hides, on top of branches, just to see what kind of temps I'm looking at throughout. This allows me to create these little micro climates and gives my animals plenty of choices when it comes to temperature and humidity.
If I stick the probes with the silicone, would they come off easily?