Mae Hong Son is best visited between November and February when the town is at its coolest and most beautiful. During the rainy season (June to October), travel to the more remote corners of the province can be difficult because there are few paved roads. During the hot season (approximately February to May), Mae Nam Pai valley fills with smoke from swidden agriculture. The only problem with going in the cool season is that the nights are downright cold – you’ll need at least one sweater and a thick pair of socks for mornings and evenings.
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