A quote from The Book of Zohar – regarding Klipot, which can be either harmful or helpful.
There are three Klipot, encompassing all kinds of Dinim (Judgments) and the Klipot in the worlds:
a) “Stormy wind,” regarding Malchut from the aspect of Din (Judgment) before being sweetened with Bina.
b) “Big cloud,” regarding Dinim that are revealed in the left line, when they illuminate without the integration of the right.
c) “Burst of flames,” regarding the Dinim de Malchut which ascended to Bina.
All the types of calamities and punishments that befall Israel, are from these three Klipot. However, just as they are damaging to Kedusha (Holiness) when Israel is not worthy, when Israel is worthy, they provide assistance to Kedusha, and all the Mochin are increased and fulfilled with their help.
Accordingly, we distinguish between two aspects of them (the Klipot):
a) When they are harmful to Kedusha, they are called “stormy wind,” “big cloud,” “burst of flames.”
b) When they are helpful to Kedusha, meaning when Israel is worthy, then those same three forms themselves of the Klipot are called Klipat Noga, and that is the fourth Klipa, concerning that which has been said: And Noga surrounds it. Because all of the Orot de Kedusha that appear in Mochin de Kedusha, surround and shine upon that Klipat Noga, and so it is that Klipat Noga separates and abolishes the three Klipot, so that they cannot again harm Kedusha.
(“New Zohar,” Parashat Yitro, item 348)