We did a very similar Itinerary over the holidays last year on the 12-22 sailing of the Celebrity Zenith. My guess is that Feb. would be a bit better weather and more of the plant life will be leafed out and in bloom. That will be near the end of their summer months. November would be similar to the Northern U.S. in May.
The flora will be a bigger issue in Chile. Much of Argentina is quite barren and there is little or no plant life to see. For instance, the weather in Chile in late December was much like our weather here in Portland would be in June.
If you just reverse the seasons and think about climates as they relate to lattitude, you'll get a good idea of the weather. Expect many days when the weather is about 50 degrees f. Be sure to take an all weather coat that has some rain protection. It's a wonderful trip, but some cruisers came unprepared for the weather.
You might want to read my review of the Zenith on this website. If you have specific questions, feel free to e-mail me.
If you have an overnight in Buenos Aires, do not miss the "Senor Tango" tango show in the city. It is a fabulous dinner and show that was the highlight of our trip. There are other tango shows but Senor Tango is the best by far. The dinner and show lasts from 8:00 P.M. until about 12:30 A.M. The entertainment, food, wine, and transportation are included at a modest price of about $40 or $50 depending on the exchange rate. The show depicts the history of the tango. There are many outstanding dancers, singers, two complete tango orchestras, and yes a dancing horse on stage too! The food was far better than anything served on the cruise ship. The never ending bottle of cabernet was excellent in quality as was the champagne served with dessert in our private box, while viewing the last half of the show. The theater is magnificent!
We did a cruise on the Ryndam, January and February of this year. It started in San Diego and included several days in the Antarctica. It was a fabulous itinerary and I would agree on the later date. Our weather was excellent, except for some rain in Pureto Montt and drizzle in Ushuaia. Neither kept us from enjoying our days. We saw so many birds, had two birding experts on board doing lectures/viewing, and saw penguins nesting and playing just a few feet away from us. We also saw whales at a distance. All of the ports were unique and worth exploring. Have a wonderful trip!