快晴(かいせい)

かいせい
noun
clear weather, fine weather
1. clear weather, cloudless sky
Weather condition with a completely clear, blue sky and no clouds.
今日(きょう)は快晴(かいせい)で気持(きも)ちがいい。
It's clear and beautiful weather today, which feels great.
運動会(うんどうかい)の日(ひ)は快晴(かいせい)だった。
The day of the sports festival was perfectly clear.
快晴(かいせい)の空(そら)の下(もと)でピクニックを楽(たの)しんだ。
We enjoyed a picnic under the clear blue sky.

快晴(かいせい) specifically refers to completely clear weather with no clouds, stronger than just 'good weather.'

Weather vocabulary hierarchy:

  • 快晴(かいせい) (perfectly clear, cloudless)
  • 晴(は)れ (sunny, fine weather - may have some clouds)
  • 曇(くも)り (cloudy)
  • 雨(あめ) (rain)

In weather forecasts, 快晴(かいせい) indicates cloud cover of 10% or less.

general
Added 2026.1.13 21:17 · Revised 2026.2.3 10:15
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