welcome rain; blessed rain; rain after a long dry period
A set phrase for rain that comes as a relief, especially after a drought or dry spell. Often carries a nuance of gratitude or divine blessing.
Since the drought continued, the welcome rain is truly appreciated.
For the farmers, it turned out to be a blessed rain.
Compound of 恵み (blessing, grace) + の (possessive particle) + 雨 (rain). The exact origin is uncertain, but it is a natural expression for rain perceived as a gift or mercy.