I noticed that whenever I went back and forth between my Windows 8 partition and my Ubuntu install, my clock would get all messed up. I thought it was because the time in my BIOS was lagging behind (like, a lot). It turns out that there’s a conflict since Linux systems store the time as UTC while Windows does something else.
The fix was pretty quick and easy:
You’ll want to make Linux use ‘Local’ time:
sudo nano /etc/default/rcSAdd or change the following section
# Set UTC=yes if your hardware clock is set to UTC (GMT) UTC=no
Source: