Whilst it is possible to cycle in Chiang Mai all year round the cycling is affected by the weather and the burning season.
The good news for those in the northern hemisphere is that the best cycling is to be had during the northern winter with pleasant temperatures, clear blue skies and minimal rain being the order of the day from mid-November to early February. In fact the cycling during this time is probably as good as anywhere in the world which is why more and more western cyclists are choosing to escape the cold back home and over-winter in Chiang Mai. There will be many more cyclists in town during this time with a rise in the number and variety of rides published as well as the number of riders on each ride.
Mid-February, temperatures begin to rise and the burning season begins which will start to affect air quality. How bad and how early the air starts to get bad will vary from year to year but by the beginning of March, it is usually noticeable and most of the temporary visitors will have returned home. The number of rides published will be reduced and it will only be the hardcore of year-round residents who will generally be riding.
By the middle of April the air has generally started to improve but it tends to be very hot. The last two years we have had temperatures in excess of 40 degrees centigrade in the afternoons. Rides tend to be shorter and earlier so as to avoid the afternoon heat.
The wet season will generally start some time in May and finish some time in October. When exactly will vary from year to year. The wet season can be a nice time to ride and we get some visitors from the southern hemisphere joining us for group rides at this time. The temperatures are a lot more pleasant than during the summer months. Yes, of course you may expect to get wet occasionally and when it does rain it is likely to be torrential but the rain generally doesn’t last for long and more often than not falls in the afternoon bringing cooler temperatures.
Optimistic winter migrants will start to arrive again in late October, hoping for an early end to the wet season and onset of the cooler, drier winter season and the numbers of group rides and riders will start to pick up once again.