"Seriously, if you know a way to get sensible biome transitions with biome appropriate weather and monster encounters in less than an eighth of a page, let me know."
What about small chart, where horizontal is temperature and vertical is moisture (or vice-versa). And when you travel to another area by conventional means for the first time, you move one step in a random direction. A loose idea but maybe it's possible? Not sure how to make the encounters also fit though.