Valmiki Ramayana Yuddha Kanda Sarga 100 Shloka 30

तदा then, प्रथमम् first, आकाशम् the sky, शरान्धकारम् darkness of the arrows, चक्रतुःcovered by, तपने sun, अस्तंगतेचापि though had set, उथतितौ even when it rose, महामेघाविव huge clouds

Then the sky covered with darkness of arrows was like two huge clouds rising even though the Sun had set.