I’ve never been to the penninsula side. but January in McMurdo starts off as the warmest time of year but rapidly begins to cool down. Two years ago it hit 50F on new years day. The peninsula is Way warmer than us. They have open water all year so I would expect that temps would be above freezing. The passage from Argentina brings you through the Drake Passage, which has been said has the worst weather in the world. Where we have about the driest weather on earth, expect the peninsula to be much wetter.