1. A whirlwind of chariots (5-18)
The Lord was bringing on Judah disaster and destruction from the north, that is, Babylon. King, officials, priests and prophets would be appalled since they all expected peace (9-10). Jerusalem's only hope was to wash the evil from her heart and be saved (14). This disaster was the fruit of sin and rebellion against the Lord, and there was no escaping it (17-18).
2. A terrible vision (19-31)
In a vision, Jeremiah heard the battle trumpets and saw the coming devastation, desolation and ruin, and he was in anguish and agony (19). Fine clothes and makeup would not avert the disaster. The pain would be worse than a woman in labor. It's truly terrible to have God's hand of protection removed.