My Macbook Pro 13" early 2011 has been running fairly cool for the last 4 months, about an average of 32-40C. However, within the last few days, the average temp has gone to an average of 45 - 52C, with the highs being in the 90s! I have tried using SMC fan control, but even at max my temps don't go below 45. I don't run intensive applications. I have been watching my CPU load for weeks as a hobby, and I know that I'm not running anything to put this kind of load. What's going on?
Due to the thermal mass it is not possible to have temperature spikes.
If that is the case please verify the software you are using to get the temperature readings.
Also please consider that the conversion Algorithm from temperature diodes readout requires calibration, that in your case was probably not done.