avalanche
A large mass or body of snow and ice sliding swiftly down a mountain side, or falling down a precipice.
A fall of earth, rocks, etc., similar to that of an avalanche of snow or ice.
(by extension) A sudden, great, or irresistible descent or influx; anything like an avalanche in suddenness and overwhelming quantity.
To descend like an avalanche.
To come down upon; to overwhelm.
To propel downward like an avalanche.
Swelter, following at high speed, had caught his toe at the raised lip of the opening, and unable to check his momentum, had avalanched himself into warm water.