Delete old modules from database

I am new to Hass (playing with it for around a month off and on) and am working with a Hassbian installation on my RPi3. I installed the Weather Underground component based on one of the tutorial videos I found on YouTube. I was able to add all of the different sensors I saw successfully. After deciding which ones I actually wanted to keep track of, I deleted the ones I didn’t want. Now I have the correct ones updating but the old ones that don’t need to be included still show up. I now have around a dozen yellow circles with a triangle and a name “error” under them.

I’ve read that I can use database commands to purge the data I don’t want. That is certainly an option. Since I haven’t done much yet, I suppose I could probably even delete the existing database and just let Hass figure it out. Maybe even reinstall with the new config file. However, I don’t want to do that every time I have an unwanted module/sensor obviously.

What is the best practice for purging old components/modules/sensors that are not currently valid? This is what I found for manually fixing the database:

The database is only for the history and has nothing to do with removed devices.

Take a look in Dev Tools/states if the old entities are there.
If yes, and you can’t remove the devices in Configuration → Entity Registry, you can take a look at the files in `.storage/core.*. Good to make a backup before!

If you only see badges with ‘Entity not found’, take a look here:

I’m just seeing the “entity not found”. I’ll check out your link.

I found the raw editor and it looks like the badges are actually the Weather Underground sensors that for some reason stopped working. It certainly looks like WU may not work anymore so I’ll have to look into that more. Thanks for pointing me in the right direction for the display though!