
So much of this answer depends on you, your major or minor and your own personal situation. Short-term programs suit students who cannot be gone four or five months for various reasons. However, many returning students say that once they adjusted to being off-campus, they wanted to stay longer. Remember that you are only an undergraduate student for four years. Make Study Abroad a significant part of that experience.
Students who study for the semester or year are often juniors. It's a good time to study abroad because you can take courses that fulfill major and minor requirements. Some students majoring in a foreign language go abroad second semester of the sophomore year. Some fall semester seniors go abroad then because it best fits their major such as biology, chemistry or business.
For January Term, you can find a program during any of your four years at St. Thomas.
The earlier you begin exploring options, the better. There are so many possible programs to choose from that you should plan to visit a Study Abroad Advisor a year before you actually want to be abroad.