What is the reason for His Kin'ah?
Malbim: The evils that they did to Yisrael.
What will be the great noise?
Rashi: It will be voices and thunder like it says 1 .
Radak: Eretz Yisrael will shake. So it says in Zecharyah (14:4-5) "v'Nivka Har ha'Zeisim?; v'Nastem Gei Harai? Ka'asher Nastem Mipnei ha'Ra'ash bi'Ymei Uziyah Melech Yehudah."
Malbim: It will be due to Evrah that will spread over the Klal (even those who did not sin).
Malbim (20) #1: It is an earthquake ? "v'Nastem? Mipnei ha'Ra'ash" (Zecharyah (14:5).
Malbim (20) #2: This is a metaphor for the great war and noise of cannons and weapons that will be at the end of days, that destroy mountains and fortified walls with awesome noise.
The verses do not explicitly mention thunder. (PF)