I'm pretty sure the UC's do not accept transfers. Individual schools should have the info on their websites if you can narrow it down a little bit. Or are you hoping to transfer to any school in the country???
I have been interested in transferring myself. I have made alot of calls, and even though many schools do, in fact, "say" they take transfer students (almost exclusively in year 3), the number of spots that actually become available are slim to none. In other words, a spot needs to become available via dropout, transfer, et cetera - otherwise, you are **** out of luck.
transferring between 1st and 2nd year is very rare. i personally have never heard of one happenening.
i actually transferred between my 2nd and 3rd because my significant other was in that particular town and was also a resident at the hospital. the few other transfer students also had very similar reasons. the people that transfered out of my old school had husbands and fiancee's where they were going.
most schools only take transfers for extenuating circumstances. weather, quality of education, etc probably won't get too far with the admission committee.
not to say that i wouldn't look into it, but something to keep in mind. maybe you should look into getting a husband/wife in your city of choice! just kidding......