Despite the chill, residents continued their daily struggle to earn a living, adapting to conditions rarely felt in the tropical south.

On Pham Van Dong Boulevard, Nguyen Ngoc Tan, 42, stayed awake through the night guarding pots of ornamental apricot trees, bundled in thick clothing and a wool hat.

Tan said the colder weather had made his work harder but also brought a sense of novelty as the Lunar New Year approaches.

Vietnam's Lunar New Year, or Tet, is the country's largest annual holiday and typically drives a surge in demand for decorative plants, including ornamental apricot trees. The holiday is due around mid-February.

Several kilometers away in the Hang Xanh area, Dai, a 78-year-old migrant from northern Hai Phong City and his wife Hoa collected discarded plastic bottles and cardboard late into the night.

Relying on the work for extra income, Dai said the cold reminded them of home.

In Binh Thanh Ward, Tran Ngoc Chuc, 66, from Can Tho City, said she continued to wake before dawn to water flowers for sale.

After nearly 30 years in Ho Chi Minh City, she was not used to the cold and had little choice but to adapt.

"Every once in a while, it's fun to feel Ho Chi Minh City as cold as Da Lat," said a resident. 

"When I opened the door this morning and felt the chill in the air, I had to put on a windbreaker and wrap a scarf around my neck to keep warm," they added as the cold air lingered into the morning, an unfamiliar sight in a city better known for year-round heat and humidity.