.Japanese NHK TV showed these images today (22 March in Japan). Some areas are supposedly 128 degrees C. They also mentioned a core temperature, but I must have heard it wrong. I thought I heard 300-some degrees C. Can't be right. Black smoke has been coming out of reactor 3.
NHK TV image
Fukushima Reactors 1 through 4 in false-color IR. Blue and green are cool, orange and red are hot, white is very hot
Closeup of Reactor 3