Weather in Thailand in October
Hot and wet or hot and dry?
If at all possible, you want to organise your holiday in Thailand so that you're spending October in the Central, North and Northeast regions. October on the islands — any of them — is wet. The weather in Northern Thailand in October though, is lovely. Less rain, cooler temperatures and not too crowded — what more could you want.
Bangkok and Central Thailand
Bye bye rain! You'll still get some rain in October in Bangkok and Central Thailand but the wet season is in full scale retreat by this stage. If the wet season was a very wet one, there may still be flooding in Bangkok and elsewhere if the Chao Phraya River swells over its banks, but that doesn't happen every year.
October on Ko Chang sees the rainfall halve again while the temperatures level of at low 20s to low 30s where they'll stay for the rest of the year. You'll still be seeing some rain on Ko Chang in October, but it's much more tolerable than the previous couple of months. November is even better.
Less rain and continuing moderate temperatures are what October brings to northern Thailand weather wise. Mae Hong Son and Pai are particularly pleasant this time of year — and not too crowded either.
The northeast is really starting to dry out come October — especially in the eastern regions, though the west will still be seeing a bit more rain. Temperatures will continue to fall, albeit slightly, from September.
October brings solid rain to most of Thailand's Gulf coast. Ko Tao in particular gets pretty average weather in October, but Ko Samui and Ko Pha Ngan also get a bit of a lashing. The mainland coast gets slightly less rain, but only marginally less. Stay in the north if you can.
As with the Gulf Coast, expect rain, rain and more rain. If you're lucky the wet will break halfway through the month, but if you're out of luck you can expect rain right to month end. On a positive note, it does rain less than in September.