The best time to visit Kengtung is November to February, when the highland climate is cool and dry. Temperatures at this altitude — around 800 metres — drop noticeably at night, so a jacket is essential. Days are clear and the light is at its best for the old town's wooden architecture and temple compounds.
March and April are hot and hazy, with smoke from slash-and-burn agriculture in the surrounding hills sometimes reducing visibility. The monsoon runs from May through October, bringing heavy rain and turning the mountain roads — particularly the route from Tachilek — into mud. Hill tribe trekking is essentially impossible during the wet months. Kengtung itself becomes lush and green in the monsoon, but travel logistics are significantly more difficult.