Hi there! I would like to know what is the weather like, say from 5th -15th Nov 2008 at Shinjuku?

Just wondering if i should bring thick clothes or not.

Thank you.

Can be cool but not cold. A jacket of some sort will be fine. Daytime, if it is sunny, can be very warm, but cloudy or rainy days and nights are cool.

You won't need any winter clothing. Just a jumper - take it off when sunny and warm and a jacket for the evening. Daily highs around 15 to 20C (60-70F), lows around 10-15C (50-60F).
As Shinjuku is a very built-up area of Tokyo, it will be just right indoors. An umbrella is always handy, but most shops sell you one for 200-500 yen and your hotel will probably lend you one.

Thank you kim and Alec. Appreciate your help.

I would like to say that this year's weather has been totally crazy all over Japan. I'm pretty sure you won't need a winter coat -- but you might want to take some clothes that you can layer, just in case it gets really cold. (like two long-sleeve shirts that you can wear under a jacket). You can get hats pretty easily in Japan, if it should happen to turn chilly (hats keep in the body heat pretty well).

Thanks Tokachim...appreciate the given tips!