Components or weather conditions (8)
I believe the answer is:
elements
This clue is a double definition.
'components' is the first definition.
('element' can be a synonym of 'component')
'weather conditions' is the second definition.
(I've seen this before)
(Other definitions for elements that I've seen before include "Fire, air, earth, water" , "Nitrogen and oxygen, e.g." , "Basic principles of the weather" , "Component parts" , "First principles of the weather" .)