Metrum 3

Meter: Dactylic hexameter alternating with dactylic tetrameter . The last foot of the tetrameter is always a dactyl.

line 1

discussa: discussa . . . nocte: ablative absolute.
nocte: discussa . . . nocte: ablative absolute.

line 3

ut: "just as," introduces a simile that fills the rest of the metrum: "just as, when . . . (lines 3-6), if Boreas (lines 7-8). . . , [then] Phoebus flashes (lines 9-10)."
glomerantur sidera: obscure; sidera may mean "bad weather," but some emend to nubila.
Coro: < Corus, the north-west wind.

line 4

polus: "the arch of heaven."

line 5

caelo: dative of place to which (a poetic usage).
uenientibus astris: ablative absolute.

line 7

hanc: sc. noctem.
Threicio: "Thracian."
Boreas: nominative, "the north wind."

line 8

reseret: < resero, "unbar, unlock."

line 10

ferit: < ferio, "strike, smite."