Yushui, Rain Water, is the second solar term, at the sun's longitude of 330 degrees, around the nineteenth of February. It is a principal (zhongqi) term, one of the twelve major markers that anchor the lunar months, a month being required to contain its principal term. Its name announces the shift from snow to rain as the air warms, the moisture the early crops need. In the farming almanac it is a time for tending winter wheat and preparing for spring sowing, and in some regions it carries family customs of honouring parents and elders. Being a solar marker, it falls on nearly the same Gregorian date each year. These are the observances of the East Asian agricultural tradition, resting on the division of the tropical year into twenty-four solar terms of fifteen degrees each.
Yushui, the Rain Water term, falls at the sun's ecliptic longitude of 330 degrees, around 19 February, and is a qi, or major, term, the second of the twenty-four and the counterpart major term to Lichun's sectional opening. Its name signals the point in the traditional agricultural calendar when precipitation is expected to shift from snow toward rain across much of the North China Plain, where the solar term system originated, though the same fixed calendar is applied across China's much wider range of climates, with correspondingly uneven fit to local conditions in the south or in the far north. Traditional pentad lore associated with this period describes otters beginning to catch fish and lay them out, geese flying north, and plants and trees beginning to bud, signs read together as marking winter's genuine retreat.