Revelation 8:6–13 follows a lengthy hush in heaven, after which seven angels receive seven trumpets and another angel mixes the prayers of the saints with incense. After emptying the censer of incense, he fills it with fire and casts it down to the earth. Thunder, rumblings, lighting, and an earthquake ensue. Now four of the seven angels blow their trumpets with disastrous effects on earth.
For a more detailed summary select the link below.
“Revelation 8:13” Bibleref.com
What does Revelation 8:13 mean? | BibleRef.com
13 I saw, and I heard an eagle, flying in mid heaven, saying with a loud voice, “Woe! Woe! Woe for those who dwell on the earth, because of the other voices of the trumpets of the three angels, who are yet to sound!”