post-holiday return traffic jam
Refers specifically to the heavy traffic congestion that occurs when many people return home at the end of a multi-day holiday period, such as Golden Week, Obon, or New Year's. The term is a wasei-eigo compound of 'U-turn' and 'rush'.
wasei-eigo (Japanese-coined English), from U-turn rush
On the last day of Golden Week, the expressways were heavily congested due to the post-holiday return rush.
To avoid the return traffic jam, I decided to go back a day early.