It's tricky to classify Asian skin. In general, yellow is warm,

However, there's warm yellow and cool yellow.

Here is a good article -

http://musicalhouses.blogspot.com/2010/01/undertones-for-asians-how-to-tell-if.html

It could be confusing.  I usually don't worry about cool or warm, instead, I just eye ball, if something looks good on me.  It's not a precise science.  I've found colors from either families look good on me.  It depends on the surrounding and mood:).  It's more important that the clothes, shoes, makeup and accessories are coordinated.