Working on preliminary plans for a trip to Thailand next year and trying to figure out the "when" part. We are thinking an itenerary would include Bangkok, Chiang Mai and then one of the island resort areas (Phuket or Ko Samui-ish) over the course of 12-15 days. Work precludes any travel from January-early June, but mid-June through November is very doable. Not a big fan of crowds and generally enjoy traveling in shoulder season when possible. That said, all the reading I've done indicates that November-February are prime-time but also dramatically more crowded and expensive. Mid-June is supposed to be the beginning of the rainy season, and I've also read that it may not be a great time to do a Trek in the North (Chiang Mai area) which is something that is absolutely on my "to do" list. I'm not afraid of a shower here and there, but I do not want to venture half way around the world to hang out in the middle of a non-stop monsoon for vacation. So I guess my question is, how rainy is rainy season and does it render a fun trip not so do-able? Thanks!

Here's the best website for weather data: www.weatherbase.com

If you can go in November, I would consider it ideal. Yes, it's more expensive than some times of the year (but not as expensive as December-January.

If you can do November, I would try for that. Hotel rates go up after October 31, but not as much as in the High season. November is the shoulder season. Also, there are some very good hotels for decent rates in November, especially in CM. We've gone in November several times and crowds were not an issue at all. Actually, the second half of November is a perfect time to go. We're headed back there at that time this year. Phuket/Krabi is doen with the rain by then.

I think in the Chiang Mai area, September and October are the worst months for rain.

I was there in July for 2 weeks and there were occasional showers and occasional heavy rains, but I don't recall it ever lasting more than 30-40 minutes.

Most of the time it was sunny and warm.

Yes I too recommend November if you can. However we were in Bangkok and Chiang Mai in July/ August and on some days there was a short lived downpour in the late afternoon but it wasn't enough to hamper any sightseeing. Have fun!

i ahve been in thailand as late as june 21 on two recent successive years.....the weather was beautiful, with a one hour shower in the late afternoon or rain all nite....but the days were nice....after lunch it clouded up...

november is fabulous....i would not consider anything before oct 15 however...prices change quite a bit on nov 1 for hotels....it is never overrun with tourists except at the holidays...

November is your best choice. If you read the Bangkok Post you will see that they have had major flooding over the last 2 months in several regions and are expecting possible flooding in Bangkok because of high tides at this time of year.

Just returned from Thailand (Sept 28-Oct 1) and only had rain in BKK here and there, but not enough to ruin anything. CM was clear but very hot. The rates and crowds are down at this time of the year. Not sure about S. Thailand

In general for beaches/islands June to Sept Gulf area, Koh Samui/Tao, Koh Chang or the mainland coastal beaches. October is always a tricky month as it is when the seasons change.