The 24 Solar Terms
대서
大暑
Major Heat · Summer
In 2026: Thu, July 23
Solar terms shift by about a day from year to year; this date is for 2026 (Korea Astronomy and Space Science Institute).
What it means
The hottest time of the year.
Weather around this time
Heat waves and tropical nights.
Seasonal food and customs
Samgyetang and other hot soups for the dog days (boknal).