Northern Thailand is a land of temperature and weather extremes. Being farther away from the ocean, however, does mean that humidity is generally lower than in the nation’s more southern areas. Humidity can still, though, occur. Average temperatures are often lower than in Central, Eastern, and Southern Thailand too. Many visitors are drawn all year round to the undulating mountains, the abundance of waterfalls, the lush jungles, the rich culture, and the laid-back lifestyle.
The hottest months are from February to June. Dry and sometimes dusty, the landscapes can look rather parched and some of the region’s waterfalls are dry. While average temperatures during the hot season are usually in the low 30s, the mercury can soar to the early 40s on some days.
In Chiang Mai, this is also the time that is sometimes referred to as the smoky season or burning season. A combination of agricultural practices whereby farmers burn the fields ready to plant the next crop, vehicle pollution, and little rainfall makes smog hang thick in the air. This can be an unpleasant time to explore the city.
December to February, with its dry conditions and fairly cool temperatures, are the most popular months for visiting Chiang Mai, Chiang Rai, and Mae Hong Son. Night-time temperatures can plummet below 10°C, especially in the mountains, so visitors will need to pack warm clothes. The daytime temperatures are often in the low 30s, providing terrific conditions for trekking in the wildlife-rich jungles, swimming in waterfalls, and visiting remote hill tribes. Landscapes are still verdant and lush following the rainy period. Motorbike adventures are popular in Northern Thailand, and this is usually the safest time for a road trip.
The rainy season in Northern Thailand offers great views of rolling countryside complete in all its green glory. Sudden downpours and the increased risk of flash flooding and landslides in some areas can present dangers though. Rains usually pass quickly, but being caught in the jungle or on a mountainous road on a scooter definitely isn’t fun. Those looking to enjoy water-based activities, such as rafting, will, however, find the rivers at their fullest during the rainy season. The rains present few problems for tourists who are primarily interested in temple hopping and visiting cultural attractions.