Rashi on Zechariah
And if the family of Egypt does not go up and they do not require rain, for the Nile comes up and waters it [i.e., the land of Egypt].
Rashi on Zechariah
it shall not [rain] upon them Their rain shall not be upon them; i.e., the Nile will not water them, and so did Jonathan render: The Nile shall not ascend upon them.