April to June and September to December are the most comfortable times in Hanoi. April is hot with temperatures around 30 degrees C, but sunny weather is common; September to November is slightly cooler, with temperatures around 25 degrees C, and there are many sunny days. June is a very hot month with temperatures around 40 degrees C, and the rainy season is from June to August. December is cool and misty, and it is cold and below 10 degrees C from the end of December to March, so bringing a coat, jacket, scarf, etc. is recommended.

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If you’d like to learn more about the “average lifestyle” of Vietnamese people, please also check out this article.

Understanding the Average Vietnamese Consumer A Rapidly Growing Market Where “Youth” and “Practicality” Coexist: Decoding the Fundamentals of Vietnamese Consumers Through Data
・A young average age and high birth rate
・Vietnamese people who prioritize “practicality”
・Growing health consciousness
and more

Reference
Tokyo's climate
Weather Altas "Monthly weather forecast and climate Tokyo, Japan"
Retrieved August, 2024, from https://bit.ly/3dBbSTF

Hanoi's climate
Weather Altas "Monthly weather forecast and climate Hanoi, Vietnam"
Retrieved September, 2024, from https://bit.ly/2XJ5F2w

Comment
Vietnam National Administration of Tourism, "Official Website Vietnam Tourism"
Retrieved September, 2024, from https://bit.ly/2EiMs0h