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This paper revealed a physical connection between the antiphase variation in the preceding autumn Tibetan Plateau (TP) and Lake Baikal snow cover anomalies (TBSA) and the following winter North Atlantic Oscillation (NAO) on interannual time scales during 1979–2021. The antiphase variation in TBSA, accounting for 44% of the total years, has a dipole structure in autumn, which prolonged into the following winter. The persistent antiphase TBSA associated diabatic forcing, disturbances and transient eddies favor a double wave train structure spanning the TP (east of Baikal) and North Atlantic from autumn to winter. Amid the wave train, the circulation anomalies over the North Atlantic extract more energy from the basic flow due to the seasonal increase in the westerly jet, which further evolves into the winter NAO pattern. Our results provide new insights into the formation and projection of winter NAO from the perspective of subtropical and extratropical Eurasia snow. Plain Language Summary: A robust link exists in the preceding autumn antiphase Tibetan Plateau (TP) and Lake Baikal snow cover anomalies (TBSA) and the winter North Atlantic Oscillation (NAO) during 1979–2021. There are 44% years of antiphase variation in TBSA in autumn, which shows a dipole structure with one positive center over the TP and another negative center over the Baikal. Larger (smaller) snow cover over the TP (Baikal) stimulates a local low (high) pressure system via diabatic cooling (heating). Due to the jet waveguide effect, the antiphase TBSA associated diabatic forcing and perturbation along the subtropical westerly jet favor the atmospheric wave train spanning the TP and North Atlantic. The antiphase TBSA associated transient eddies along the extratropical belt contribute to the atmospheric wave train lying between the eastern Baikal and the North Atlantic owing to the eddy‐flow interaction. Along with the seasonal increase in the subtropical westerly jet from autumn to winter, the geopotential height anomalies in the double wave train associated with the antiphase TBSA gradually develop into the winter large‐scale NAO circulation through more energy extraction from the stronger basic flow. Key Points: A robust link of winter North Atlantic Oscillation (NAO) to the preceding fall antiphase Tibetan Plateau‐Baikal snow cover anomalies (TBSA)The antiphase TBSA associated diabatic forcing, disturbances and transient eddies favor a double wave train structure around 30°N and 60°NMore energy extracts over the North Atlantic due to the seasonal increase in the westerly jet, favoring the development of the winter NAO [ABSTRACT FROM AUTHOR]