As far as the northern SC coast, Pawleys Island/Georgetown region, it can be pretty cold there for long stretches during the winter. Sometimes accompanied by cold wind. Me personally, I wouldn't stop until at least Savannah, Ga. And better yet, as someone suggested Palm Coast, I rode in St. Augustine this past January. Seems to be fairly bike friendly, lots of bike lanes around there. Even right in town motorists seemed pretty tolerant. Also rode out in the country toward the St. Johns river. Pretty country & just a little south is Palm Coast.