Brrrrrrrrrrr

So the recent weather got me thinking about warm and cold clothes to take with travelling.
(Also I watched the Michael Palin Himalaya when he does Everest base camp and felt inspired and itchy-footed as always!)
When we travel through Tibet, its going to vvvvvery cold, but the further South we go, the warmer we get and less clothes we'll wear... But eventually we will be heading south again through Japan, and could get to some pppretty cold places in the North.
Not sure what the best thing to do is, and I can imagine in a steamy Cambodia we might be quite pissed off that we have to carry the jackets etc in our luggage (on our backs ) the whole time.
Judging from forums, a lot of people just buy as they travel, or send stuff home- but both cost money which will be tight already so I'm not keen.
Not sure what the best thing to do is........?

Either way, I know its probably not great at keeping you warm... but i want this Jacket from Uniqlo..(only £19.99-whoo!)...