I am on Debian and have used the dpkg-reconfigure tzdata command, however it changed the universal time and not the local time. My clock on xfce still displays the wrong time. Right after setting the right time it displays this:
Current default time zone: 'America/Los_Angeles' Local time is now: Sun Jan 17 04:50:23 PST 2016. Universal Time is now: Sun Jan 17 12:50:23 UTC 2016.
My time is 4:50 am
It seems to have the correct timezone, but it is eight hours off :(