Valmiki Ramayana Aranya Kanda Sarga 23 Shloka 1
Original Shlokaतस्मिन्याते बले घोरमशिवं शोणितोदकम्। अभ्यवर्षन्महामेघस्तुमुलो गर्दभारुणः।।3.23.1।।
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गर्दभारुणः dark like the colour of an ass, तुमुलः fierce, महामेघः huge cloud, तस्मिन् that army, याते marched, तत् there, घोरम् dreadful, बलम् army, अशिवम् inauspicious, शोणितोदकम् water red as blood, अभ्यवर्षत् rained.
As the army marched from there (Janasthana) a huge dark cloud of the colour of an ass rained dreadful inauspicious water, red as blood. Khara sees dreadful omens.