I've been testing this website today: losethevery.com.
It's a nice idea, but be very very careful with this type of random word list/generator.
The problem with synonyms is that they are rarely EXACT synonyms.
For example in this video you'll see this example:
"very + dirty" = "obscene"
Unfortunately, 'obscene' means 'offensive, rude and shocking'.
You can't say your shoes are 'obscene' after going for a muddy walk, or your kitchen is 'obscene' after cooking dinner.
So I would recommend sticking to the extreme adjectives that you know are correct e.g. cold - freezing, dirty - filthy, hungry - starving etc.