This morning I was rudely awoken in the wee hours by whining winds. Grumpily I dragged myself out of bed and looked over to my calendar, glancing the date to be October 23.
A little note Soukou 霜降 sat in the box meaning ‘descent of frost’ thinking of the storm raging outside my window I chuckled to myself and though ‘yeah sounds about right’.
Unlike much of Asia the Gregorian calendar has been in use in Japan since 1873 when it superseded the Chinese lunisolar calendar which had been in place for almost 1200 years.
The Chinese calendar divided one solar year into twenty-four points signifying significant celestial events such as solstices, equinoxes and the beginning of the seasons or natural phenomenon. In Japanese these are referred to as Nijushi Sekki 二十四節季 and are still retain some importance in modern society.
The Nijushi Sekki or seasonal days are as follows:
Risshun (立春): February 4—Beginning of spring
Usui (雨水): February 18—Rain water
Keichitsu (啓蟄): March 5—Awakening of Insects (from hibernation)
Shunbun (春分): March 20—Vernal equinox, middle of spring
Seimei (清明): April 4—Clear and bright (skies)
Kokuu (穀雨): April 20—Grain rain
Rikka (立夏): May 5—Beginning of summer
Shōman (小満): May 21—Grain Fills
Bōshu (芒種): June 5—Grain in Ear
Geshi (夏至): June 21—Summer Solstice, middle of summer
Shōsho (小暑): July 7—Little Heat
Taisho (大暑): July 23—Great Heat
Risshū (立秋): August 7—Beginning of Autumn
Shosho (処暑): August 23—End of Heat
Hakuro (白露): September 7—Descent of White Dew
Shūbun (秋分): September 23—Autumnal Equinox, middle of Autumn
Kanro (寒露): October 8—Cold Dew
Sōkō (霜降): October 23—Descent of Frost
Rittō (立冬): November 7—Beginning of winter
Shōsetsu (小雪): November 22—Little Snow
Taisetsu (大雪): December 7—Great Snow
Tōji (冬至): December 22—Winter Solstice, middle of Winter
Shōkan (小寒): January 5— Little Cold
Daikan (大寒): January 20—Great Cold
Many zassetsu days occur in multiple seasons:
Setsubun (節分) prefers to the day before each season, or the eves of Risshun 立春 (Spring), Rikka 立夏(Summer), Risshuu 立秋 (Autumn), and Rittou 立冬 (Winter). However it is most commonly attributed the day before the first day of spring (risshun). Setsubun falls on the 3rd or the 4th of February on the calendar today.
Doyō (土用) refers to the 18 days before each season, especially the one before fall which is known as the hottest period of a year.
Higan (彼岸) is the seven middle days of spring and autumn, with Shunbun at the middle of the seven days for spring, Shūbun for fall.
Shanichi (社日) is the Tsuchinoe (戊?) day closest to Shunbun (middle of spring) or Shūbun (middle of fall), which can be as much as −5 to +4 days away from Shunbun/Shūbun.