They display a tendency to burrow in the snow if the wind is cold and violent.

Poorgas do not occur at regular intervals, but are most prevalent in February and March.
A few years ago a party of Koriaks crossing the great tundra north of Kamchatka encountered a severe storm.

It was of unusual violence, and soon compelled a halt.

Dogs and men burrowed into the snow to wait the end of the gale.

Unfortunately they halted in a wide hollow that, unperceived by the party, filled with a deep drift.