‘The first woe is past, behold there come two more woes hereafter.'
As with the seals, while the first five are concurrent, the sixth leads up to the end of time. (The seventh is the end of time, the last trump). Thus while the first woe is concurrent with what goes before, the second and third finalise history. The awfulness of the first woe is brought out in this warning, and what more woeful than Satanic activity? But there is further emphasis on the awfulness of the next two woes.
The Sixth Trumpet Sounds - The Second Woe.