On December 18, Chiang Mai city experienced cool weather, with temperatures averaging 17-28°C. Surrounding districts recorded even lower temperatures, dropping to 14-15°C in some areas. At Doi Inthanon and Kew Mae Pan in Chom Thong District, the weather was clear, and air quality was excellent. The grass-top temperature on the summit measured 4.6°C, with a low of 5°C, classified as very cold. Kew Mae Pan viewpoint recorded a temperature of 8°C, attracting over 4,000 visitors clad in warm attire for the chilly experience.
The general weather in Doi Inthanon National Park remained cold throughout the day, with an average temperature of 11°C. Both Thai and international tourists enjoyed the crisp climate while staying at park accommodations, campgrounds, and nearby resorts. Popular attractions included seasonal highlights such as terraced rice fields, natural grasslands, and vibrant hydrangea gardens, all adding to the charm of the winter season.