Wandering about, retreating before storm (6)
I believe the answer is:
errant
'wandering' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for errant that I've seen before include "Travelling in search of adventure like knight of old" , "looking for adventure" , "Travelling about or going astray" , "Quixotic" , "Sinful" .)