Prone to dust storms (4)
I believe the answer is:
arid
'prone to dust storms' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for arid that I've seen before include "Dry and infertile" , "Wadi may be this" , "Dry and parched, as with regions" , "Very dry, having little rain" , "Sterile" .)