Changing Hemispheres

Now that winter is almost here in the U.S. I would like to start flying in the Southern Hemisphere where it is late spring / summer. I know I can go to my settings page and go into general and reset the latitude / longitude to southern western or southern eastern but how do I make it stay that way while flying in South America or South Africa etc. It always goes back to Northern Western on the settings. When I go to my Time and Seasons settings it shows fall-November. If I change it to spring it jumps to May. How do I correct this?