Is there a book that can explain all these in very detailed terms? Did you take a class on this before when you said reaching back trying to remember? If so, which textbook did you use?
I cannot recall which 'book' we used - it may have been a RAF publication, some of which were excellent.
Without prying too deeply, though, 'redblue', looking at your profile, can you not just 'accept' these apparently contradictory/confusing items and live with them for PPL work? If you are looking at becoming a met man, I sugggest you contact your local aviation met office and ask them for a pointer at books. If you are going 'commercial', the training course will cover all you NEED to know (for the exam
). The ONLY reason I had to know them was in case 'Bloggs' asked me!!
I don't think I have ever used the info for real in 40yrs plus flying!