Reactor2 temperature jumped up by 120 within 12 hours
[link to fukushima-diary.com]

[snip]

The temperature of reactor2 is almost reaching 265 C.

The thermometer attached on the upper part of RPV2 recorded the rapid increase of temperature from 143.4 to 262.3 when was from 23:00 of 2/15/2013 to 11:00 of 2/16/2013.




Japan's Fukushima reactor may be reheating: operator
February 13, 2012
[link to phys.org]

[snip]

Tokyo Electric Power said one of three thermometers on the number-two reactor at the Fukushima Daiichi nuclear plant indicated gradual heating this month and reached 82 degrees Celsius (179.6 degrees Fahrenheit) Sunday. The temperature was above the 80-degree safety standard newly employed by Japan's nuclear safety authority, prompting the utility to publicise the reading and notify public agencies.

Read more at: [link to phys.org]