what is the role of ‘western disturbances’ in the Indian climate?

(i) A characteristic feature of the cold weather season over the northern
plain is the inflow of cyclonic disturbances from the west and the
northwest.
(ii) These low pressure systems originate over the Mediterranean sea and Western Asia and move into India, along with esterly flow.
(iii) They cause the much needed winter rainfall, locally known as ‘Mahawat’ is small, it is very useful for rabi crops.
These winds are called western disturbances since they come from the western part of India.