Today March 20th is Spring Equinox Day or Shunbun no hi (春分の日) in Japan. This national holiday was first established in 1948 as a day to admire nature and the love of living things. The holiday occurs on the date of the vernal equinox in Japan Standard Time and usually falls on March 20 or 21.
The three days immediately before and after Shunbun no hi is a seven day period called the spring equinoctial week or higan in Japanese. It is a boundary marking the end of winter coldness.
This is the time of year when spring break starts in Japan.