The “Start of Winter” (Lidong) is the first solar term of winter, marking the hand-over from autumn to winter. In a normal year, the cold air now brings not the crisp breezes of autumn but the high winds and falling temperatures of true winter. In a milder year, however, this seasonal change — and the strength of the cold air — may arrive less sharply.
The Start of Winter falls on 7 or 8 November each year, one of the 24 solar terms of the traditional Chinese calendar, when the sun reaches a celestial longitude of 225°.
What the Start of Winter means
The classic Collected Explanations of the Seventy-Two Pentads states: “Li means to begin; dong (winter) means to end, when all things are stored away.” That is, the autumn crops have all been harvested, dried and put into storage, and animals too have gone into hiding to prepare for hibernation. So the Start of Winter does not merely signal the coming of winter — more precisely, it marks winter’s beginning, the storing-away of all things, and the avoidance of cold.
The Start of Winter is one of the solar terms that reflect seasonal change. The ancients divided it into three pentads: in the first, water begins to freeze; in the second, the ground begins to freeze; in the third, pheasants are said to enter the water and become large clams. The meaning is that after the Start of Winter the Northern Hemisphere receives ever less solar radiation; but because some of the heat stored in the ground during the summer half-year remains, it is generally not yet very cold.
Climate at the Start of Winter
Because China is so vast — apart from the south coast, which has no winter at all, and the Qinghai-Tibet Plateau, which has long winters and no summer — winter does not begin everywhere on the same day. By the climatological standard, winter begins when the average temperature over five days falls below 10°C; on this measure, “the Start of Winter as the first day of winter” broadly matches the climate of the Huang-Huai region. In China’s far north — Mohe and the area north of the Greater Khingan Range — winter arrives in early September; Beijing already looks wintry by late October, while winter in the Yangtze valley does not truly begin until around the “Light Snow” term. On a multi-year average, November is the month with the most cold waves.
Sharp drops in temperature, and abnormally warm or cold weather, can seriously affect daily life, health and farming. It is therefore very important to follow weather forecasts and, as conditions change, to protect both people and crops against cold and frost damage in good time.