جَادَتْ عَلَيْهِ كُلُّ بِكْرٍ حُرَّةٍ فَتَرَكْنَ كُلَّ قَرَارَةٍ كَالدِّرْهَمِ
Each fresh cloud with clear, unmingled rain poured generously over it, leaving every hollow gleaming like a silver dirham.
A qarārah is a depression in the ground where water gathers. After rainfall, the filled hollows appear as little bright circles; the poet likens them to dirhams, silver coins.