Valmiki Ramayana Yuddha Kanda Sarga 108 Shloka 30

सर्वाः all, दिशः च directions, प्रदिशश्च intermediate points, तिमिरावृताः enveloped by darkness, बभूवुः remained, नभः sky, महता huge, पांसुवर्षेण shower of dust, दुर्दर्शम् to see, अभवत् obscure

All directions and intermediate points were enveloped by darkness by the shower of dust and the huge sky was obscure.