12Z GFS 10-mb geopotential and temperature animation to 384 hours.

Note that temperatures are forecast to be *positive* (+4C) at T+324h over NE Siberia.#PolarVortex

(Individual images are available on request. Working on a server access at the moment) pic.twitter.com/QjST7vkcS8

— Stephane Gentile (@FrenchScotPilot) December 9, 2018