Valmiki Ramayana Yuddha Kanda Sarga 65 Shloka 48

उल्काशनियुताः thunder and lightning, गर्धभारुणाः donkey coloured, मेघाः clouds, बभूवुः appeared, ससागरवना ocean and forests, वसुधा च earth, समकम्पत was shaken.

The clouds appeared in the colour of donkey and there was thunder and lightning. The oceans, forests and earth seemed as though shaken.