What reason does Cassius give for the terrible storm?
he believes that the gods are using these signs to warn the Romans about a "monstrous state," meaning both an abnormal state of affairs and an atrocious government Cassius compares the night to Caesar himself, who
like this dreadful night,
. . . thunders, lightens, opens graves, and roars
As doth the lion in the Capitol. (I.iii.72-74