heh, knew you were running dualboot with linux just from looking at the title
Its an incompatibility between localtime and UTC. Windows uses local by default and ubuntu uses UTC. You must set ubuntu to use localtime instead.
In ubuntu modify the file with your favorite text editor: "/etc/default/rcS"
add or change the following:
More information here: https://help.ubuntu.com/community/UbuntuTime
(scroll down to part about multiboot config)