Wiktionary
windslab
n. Snow which peels off in large slabs when disturbed, increasing the risk of avalanche.
Usage examples of "windslab".
The snow here is soft under windslab, and he must lean up, dig away a bit with his ice axe, swim up to the new foothold, dig away some more - on and on, gasping into the oxygen mask, sweating profusely in the suddenly overwarm clothing.
But the bottom of the bowl is filled with deep drifts of light, dry, granular snow, sheeted with a hard layer of windslab.