What is the comparison to clouds?
Radak: Just like clouds rise from the ground - "v'Ed Ya'aleh Min ha'Aretz" (Bereishis 2:6) - and they rise quickly, so the enemy will come on Eretz Yisrael. It says Ya'aleh, for Eretz Yisrael is higher than the other lands.
Malbim: The Ru'ach (in the above metaphor) will not disperse clouds, rather, it will come quickly like a cloud.
What is "vecha'Sufah"?
Rashi: Like a whirlwind. Radak - it is a strong wind that goes quickly. So his chariots will go! Malbim - this is faster than a normal wind.
Why does it say "Kalu mi'Nesharim"?
Radak: The Nesher flies faster than other birds, and higher than all of them - "Ka'asher Yid'eh ha'Nasher" (Devarim 28:49). Malbim - this is faster than Sufah; the horses are faster than the chariots.
Why does it say "Oy Lanu Ki Shodadnu"?
Radak: He will come to plunder us.
Malbim: We caused this to ourselves, through not listening to Navi Hashem, rather, to false Nevi'im.
