Why the weather in Korea feels pleasant recently

Fine dust is trapped in China (some say it will come to us soon)

Yellow (51-100):

Generally satisfactory, but may pose some health concerns for a very small number of people who are sensitive to some contaminants.

Orange (101-150):

Harmful to sensitive groups such as the elderly or those with respiratory diseases

Red (151-200):

Even the general public may experience health discomfort, and sensitive groups may be seriously affected.

(In Japan, apart from the earthquake, the weather is crazy)