Rain Water

Meaning

Rain Water, Yushui, is the second of the twenty-four solar terms: the Sun at 330°, about 19 February. Its name says what changes: what fell as snow now falls as rain, the frozen ground begins to soften, and the moisture that the fields will need for the year arrives. It is the first term in which spring can be felt rather than only announced.

It is a principal term, the middle of the Tiger month that Lichun opened. In the lunar calendar people celebrate by, the month that holds Rain Water is the first month, the one the New Year begins, which is why the Lantern Festival and the last days of the New Year’s holidays often fall near it.

Its three pentads are among the most vivid of the year: the otter lays out the fish it has caught along the bank, as if in offering; the wild geese fly north; the grasses and the trees put out their first buds.

In practice

• In BaZi nothing turns at Rain Water: the month pillar stays the Tiger month’s until the next opening term, Jingzhe. A birth near it is no nearer a change of pillar.
• In the Chinese calendar it names the first lunar month; a lunar month with no principal term would be a leap month.
• The Calendar marks it on its day, with the Sun at 0° Pisces, as the middle of the Tiger month.
• In the zodiac and Feng Shui the month animal and the month’s star are those of the Tiger month, from Lichun to Jingzhe.

Across traditions

• In Western astrology the Sun enters Pisces at this very moment, a water sign opening as the Chinese calendar names its rain: two traditions reading the same weeks through water.
• In Korea an old saying pairs this term with the next: at usu and gyeongchip, the ice on the Taedong river breaks; in Vietnam it is vũ thủy.
• In Japan many families set out the hina dolls around Usui, ready for the Girls’ Festival on 3 March.

Origin and history

The term belongs to the list of twenty-four that the Huainanzi gives in 139 BC, and its signs of nature to the “Twelve Months” of the Lüshi Chunqiu and the Seasonal Instructions of the Yi Zhou Shu. The otter, the geese and the buds were watched in the valleys of the Yellow River, where Rain Water is the time of the first thaw.

Its place has moved once. In the earliest Han calendars, as Ban Gu’s Hanshu records, the term of the waking insects came before Rain Water; the order was later reversed, and since then Rain Water has been the middle of the first month and the waking of the insects the opening of the second. The terms have kept that order ever since, in China and in every calendar that borrowed them.

How Ulune calculates it

Ulune takes Rain Water as the instant the Sun’s apparent longitude reaches 330°, from its table of the solar terms computed with the Swiss Ephemeris for 1800 to 2200. As a principal term it changes no pillar; the Calendar shows it on the reader’s own date. In 2026 it fell on 18 February at 15:51 UT.

Correspondences