Valmiki Ramayana Kishkindha Kanda Sarga 28 Shloka 20

विद्युत्पताकाः with banners of lightning, सबलाकमालाः closely connected garlands (rows) of herons, शैलेन्द्रकूटाकृतिसन्निकाशाः resembling the shapes of high mountain peaks, मेघाः clouds, संयुगस्थाः marching in wars, मत्ताः proud, गजेन्द्रा इव resembling elephants, समुदीर्णनादाः trumpetting in excitement, गर्जन्ति rumble.

The clouds that resemble high mountain peaks, having their banners of lightning with rows of herons as garlands give out loud peals of thunder like elephants in rut trumpet in battlearray.