I will be heading to Thailand in March...what is the weather like both day n nite?

Hot, especially in the latter part of March. Expect highs around 90-95F (33-35C) and lows aound 78-80F (25-26C). Mid-March through May is the hottest time of the year here in Thailand, but it doesn't rain too much that time of year. Have fun.

I have just come back fron Thailand and the weather was absolutely perfect and I believe this should carry on right up to April.I do not think you will have anything to worry about weather wise.Have a wonderful time I hope to go back in October.The best months are as follows: Oct/Nov/Dec/Jan/Feb/Mar to the begining of April

I am also going to Thailand in early March for 1 month.
Depending on where you go the weather will be hot, hot as always.
The weather is cooler at night but will be difficult to sleep in without A/C in your hotel room
Day time is very hot especially in April.

i was in thailand last march and it was fantastic, the weather was perfect, we didn't see a cloud!
we were in southern thailand so im sure the weather is different up north in chang mai etc.
great time of year to go, not to busy and weather= amazing