We did this cruise about 2 years ago and it was fabulous. the weather in the Canaries during the day swill be like a good English summer day, but chilly once the sun has gone down about 1630. The fireworks in Madiera are fabulous and you will need a jacket or sweater to be on deck to watch them. The men will be in dinner jackets and if you take both black and white suggest you wear black as the atmosphere can get very smoky and some gents did get marks on their white ones. For Lisbon it will be cooler and I would suggest an umbrella packed might be a good idea. We had no problmes with the stability of the ship even though the seas were abit choppy at times. Informal nights a smart summer dress or skirt for the ladies and slacks cotton shirt and tie are ideal for the men.Hope this helps enjoy your cruise.
Daytime temperatures in the Canaries will be warm but not hot. Expect low 20'sC. Evenings will cool down to around 15-18C. New year fireworks in Madeira are supposed to be very good. Whether seas will be choppy or not, who knows but there is a good possiblity at this time of the year. Oriana is quite good in heavy seas. We were on last year in a Force 12 and did not have problems, except some glasses slid off the shelf in the cabin.
We did this cruise in april and it was choppy then for first 2 days so expect some movement, and on the ship there are a few semi formal nights which is a pain for anyone who doesnt like sitting around all night in a suit' as semi formal means suit but no tie' as for the informal or casual as long as your knees arent showing long shorts,jeans or khaki or flannel trousers and casual shirt no vests. if you havent been to madeira it is great during the day, lots of walking and the cable car is magnificent but on a night it was very disappointing.