High Temps During Data Transfer?

Just now I am using my 2011 2.2 MBP and I experienced something odd, again (it happened before). It seems like whenever I plug in my external drive for Time Machine, the temps shoot up and the fans go up pretty much to high speed. Opened iStat Pro and saw 86C CPU temp with 2% CPU usage. If it matters, I also had the Apple Wireless Keyboard and Magic Mouse connected, 1680x1050 secondary display attached, running on MagSafe power, sitting on a desk in a Speck SeeThru satin, under a work lamp. Should just simple data backup be making the temps shoot up so much like that? I also just had iTunes open as well as 10 tabs in Chrome. Although it seems like whenever I do any data transfer at all it heats up. Temps are back to normal now (fans are at 2500RPM and temps are still 77C)