fairly often during the winter, my oil will do the same thing. i can also get cloudiness on my oil level glass. this is caused by the more extreme heat/cool temp differences which leads to condensation. this condensation heats up with the engine and vaporizes, hence the emulsion and cloudiness.
you may want to change your oil slightly earlier than you usually do, but ultimately this will go away when the weather warms up and is nothing to express concern over.