In story "There Will Come Soft Rain" by Ray Bradbury What is the significance of rain?

The poem communicates the idea that nature will outlast humanity and thrive once man's civilizations have been destroyed. The choice of the poem is ironic considering that the house's family has been destroyed. Their silhouettes were burned into the side of the house after the nuclear explosion. The rain in particular represents the cleansing effect of nature upon man and his technology. The family, like mankind, have lost themselves in technology and forsaken the nature which should be the core of the human condition.