A vocabulary of landscape — a landscape of words
1133 entries
cloudburst
A cloudburst is a sudden extreme downpour over a small area in a short time, the kind that drops an inch or more in a matter of minutes. The rain arrives faster than any ground can take it, so almost all of it runs off at once, which is why cloudbursts and flash floods are the same event described from two ends. They come from tall storm clouds where rising air holds water aloft until it can no longer be supported.
Etymology
The word is a plain English compound and it records a genuine old belief: that a cloud was a vessel holding water and that a downpour meant the vessel had split. German has the same picture in wolkenbruch, cloud-break. The idea is wrong in its mechanics but not far off in its effect, since a strong updraft really does hold water in suspension until it fails, and then everything comes down at once.
Notes
Slot canyons in the desert Southwest are cut by cloudbursts and are dangerous during them for the obvious reason: The storm that fills the canyon can be many miles upstream and out of sight from inside it. The wettest short-duration rainfall records on earth are cloudburst events, several of them from Réunion in the Indian Ocean.