The prices SIN-HKT are great, and with the discount airlines, 2500THB one way fares are common. It sure beats the overpriced USM and BKK fares.
But, as far as the weather goes, it's really a crapshoot. If you choose a good week, you'll be happy with clear skies. If you choose the wrong week, you may get more than a few downpoars. It's a tropical climate. As I recall, October is a wetter month than others, but each year is different . Besides the seasons rotate on the lunar month, not the Jan-Dec calendar (similar to Easter's wide date range of up to two months).
I recommend checking historical charts on weatherunderground.com as the published Thai weather is sometimes "EDITED".
And if you come and it rains a bit, so what. It's still a great place to be!
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