ごろごろ
*Roll roll...*
Japanese onomatopoeia for the sound of rolling. Most often used to express the *rumbling* sound of "rolling" thunder in the distance, and as such is the usual go to SFX for *bad weather*.
Variants include *koro koro*, *goron goron* and multiple different permutations of *goro*, *goron* and *koro* (and other variants). Use this same tag for all of them.