Charts of the day: Current and projected snow cover.
Discussion: Eurasia snow cover is off to a buoyant start as meteorological winter approaches. Snow cover is well above normal extending throughout Eastern Europe and Northeast China. Snow cover enables cold air masses to gather. The 300-hour snow cover forecast by the GFS indicates Central and East Europe snow cover increases and extends to Ukraine.
Week-2 Ahead Forecast valid December 5-11, 2023: Northwest Eurasia arctic air.
Discussion: Northwest Eurasia cold turns to arctic intensity helped in-part by deepening snow cover. Southwest Europe is warming. In-between, the storm track brings rain to Western Europe and abundant snow to Eastern Europe to Ukraine.
Week-3 Ahead Forecast valid December 12-18, 2023: Doubting the warm-up.
Discussion: In 15 days, the mega-cluster ensemble “most likely” upper air forecast indicates a cold trough lingering over Europe. ECM, GFS, and CFS V2 each indicate a robust warm pattern change. However, extensive snow cover advises caution, and the CMC projection of lingering cold is indicated.
Week-4 Ahead Forecast valid December 19-25, 2023: No major warm-up.
Discussion: While Western Europe is milder, snow cover maintains a cold bias across Western Russia.