Residents marooned on rooftops after snow melt and heavy rain causes Karasul River to burst its banks.
Threat to Salekhard and Anadyr could come even sooner - by the mid-2020s - as thaw of frozen ground is forecast to have 'devastating' impact.
Russia's coldest region is up to 20C milder than average this month, say meteorologists.
Freak climate conditions sees an abnormally warm November.
Investigation under way as mummified baby remains, bones and medical records found in disused facility.
Nuclear scientist alleged to have stolen small aircraft, but he insists he had paid for it and is the victim of an elaborate fraud.